There are outstanding evolutionary questions on the recent emergence of human coronavirus SARS-CoV-2 including the role of reservoir species, the role of recombination and its time of divergence from animal viruses. We find that the sarbecoviruses—the viral subgenus containing SARS-CoV and SARS-CoV-2—undergo frequent recombination and exhibit spatially structured genetic diversity on a regional scale in China. SARS-CoV-2 itself is not a recombinant of any sarbecoviruses detected to date, and its receptor-binding motif, important for specificity to human ACE2 receptors, appears to be an ancestral trait shared with bat viruses and not one acquired recently via recombination. To employ phylogenetic dating methods, recombinant regions of a 68-genome sarbecovirus alignment were removed with three independent methods. Bayesian evolutionary rate and divergence date estimates were shown to be consistent for these three approaches and for two different prior specifications of evolutionary rates based on HCoV-OC43 and MERS-CoV. Divergence dates between SARS-CoV-2 and the bat sarbecovirus reservoir were estimated as 1948 (95% highest posterior density (HPD): 1879–1999), 1969 (95% HPD: 1930–2000) and 1982 (95% HPD: 1948–2009), indicating that the lineage giving rise to SARS-CoV-2 has been circulating unnoticed in bats for decades.
In December 2019, a cluster of pneumonia cases epidemiologically linked to an open-air live animal market in the city of Wuhan (Hubei Province), China1,2 led local health officials to issue an epidemiological alert to the Chinese Center for Disease Control and Prevention and the World Health Organization’s (WHO) China Country Office. In early January, the aetiological agent of the pneumonia cases was found to be a coronavirus3, subsequently named SARS-CoV-2 by an International Committee on Taxonomy of Viruses (ICTV) Study Group4 and also named hCoV-19 by Wu et al.5. The first available sequence data6 placed this novel human pathogen in the Sarbecovirus subgenus of Coronaviridae7, the same subgenus as the SARS virus that caused a global outbreak of >8,000 cases in 2002–2003. By mid-January 2020, the virus was spreading widely within Hubei province and by early March SARS-CoV-2 was declared a pandemic8.
In outbreaks of zoonotic pathogens, identification of the infection source is crucial because this may allow health authorities to separate human populations from the wildlife or domestic animal reservoirs posing the zoonotic risk9,10. If stopping an outbreak in its early stages is not possible—as was the case for the COVID-19 epidemic in Hubei—identification of origins and point sources is nevertheless important for containment purposes in other provinces and prevention of future outbreaks. When the first genome sequence of SARS-CoV-2, Wuhan-Hu-1, was released on 10 January 2020 (GMT) on Virological.org by a consortium led by Zhang6, it enabled immediate analyses of its ancestry. Across a large region of the virus genome, corresponding approximately to ORF1b, it did not cluster with any of the known bat coronaviruses indicating that recombination probably played a role in the evolutionary history of these viruses5,7. Subsequently a bat sarbecovirus—RaTG13, sampled from a Rhinolophus affinis horseshoe bat in 2013 in Yunnan Province—was reported that clusters with SARS-CoV-2 in almost all genomic regions with approximately 96% genome sequence identity2. Zhou et al.2 concluded from the genetic proximity of SARS-CoV-2 to RaTG13 that a bat origin for the current COVID-19 outbreak is probable. Concurrent evidence also proposed pangolins as a potential intermediate species for SARS-CoV-2 emergence and suggested them as a potential reservoir species11,12,13.
Unlike other viruses that have emerged in the past two decades, coronaviruses are highly recombinogenic14,15,16. Influenza viruses reassort17 but they do not undergo homologous recombination within RNA segments18,19, meaning that origins questions for influenza outbreaks can always be reduced to origins questions for each of influenza’s eight RNA segments. For coronaviruses, however, recombination means that small genomic subregions can have independent origins, identifiable if sufficient sampling has been done in the animal reservoirs that support the endemic circulation, co-infection and recombination that appear to be common. Here, we analyse the evolutionary history of SARS-CoV-2 using available genomic data on sarbecoviruses. We demonstrate that the sarbecoviruses circulating in horseshoe bats have complex recombination histories as reported by others15,20,21,22,23,24,25,26. Despite the SARS-CoV-2 lineage’s acquisition of residues in its Spike (S) protein’s receptor-binding domain (RBD) permitting the use of human ACE2 (ref. 27) receptors and its RBD being genetically closer to a pangolin virus than to RaTG13 (refs. 11,12,13,22,28)—a signal that suggests recombination—the divergence patterns in the S protein do not show evidence of recombination between the lineage leading to SARS-CoV-2 and known sarbecoviruses. Our results indicate the presence of a single lineage circulating in bats with properties that allowed it to infect human cells, as previously described for bat sarbecoviruses related to the first SARS-CoV lineage29,30,31.
To gauge the length of time this lineage has circulated in bats, we estimate the time to the most recent common ancestor (TMRCA) of SARS-CoV-2 and RaTG13. We use three bioinformatic approaches to remove the effects of recombination, and we combine these approaches to identify putative non-recombinant regions that can be used for reliable phylogenetic reconstruction and dating. Collectively our analyses point to bats being the primary reservoir for the SARS-CoV-2 lineage. While it is possible that pangolins, or another hitherto undiscovered species, may have acted as an intermediate host facilitating transmission to humans, current evidence is consistent with the virus having evolved in bats resulting in bat sarbecoviruses that can replicate in the upper respiratory tract of both humans and pangolins25,32.
Recombination analysis and identification of breakpoint-free genome regions
Among the 68 sequences in the aligned sarbecovirus sequence set, 67 show evidence of mosaicism (all Dunn–Sidak-corrected P < 4 × 10–4 and 3SEQ14), indicating involvement in homologous recombination either directly with identifiable parentals or in their deeper shared evolutionary history—that is, due to shared ancestral recombination events. This is evidence for numerous recombination events occurring in the evolutionary history of the sarbecoviruses22,33; specifying all past events in their correct temporal order34 is challenging and not shown here. Figure 1 (top) shows the distribution of all identified breakpoints (using 3SEQ’s exhaustive triplet search) by the number of candidate recombinant sequences supporting them. The histogram allows for the identification of non-recombining regions (NRRs) by revealing regions with no breakpoints. Sorting these breakpoint-free regions (BFRs) by length results in two segments >5 kb: an ORF1a subregion spanning nucleotides (nt) 3,625–9,150 and the first half of ORF1b spanning nt 13,291–19,628 (sequence numbering given in Source Data, https://github.com/plemey/SARSCoV2origins). Eight other BFRs <500 nt were identified, and the regions were named BFR A–J in order of length. Of the nine breakpoints defining these ten BFRs, four showed phylogenetic incongruence (PI) signals with bootstrap support >80%, adopting previously published criteria on using a combination of mosaic and PI signals to show evidence of past recombination events19. All four of these breakpoints were also identified with the tree-based recombination detection method GARD35.
The extent of sarbecovirus recombination history can be illustrated by five phylogenetic trees inferred from BFRs or concatenated adjacent BFRs (Fig. 1c). BFRs were concatenated if no phylogenetic incongruence signal could be identified between them. When viewing the last 7 kb of the genome, a clade of viruses from northern China appears to cluster with sequences from southern Chinese provinces but, when inspecting trees from different parts of ORF1ab, the N. China clade is phylogenetically separated from the S. China clade. Individual sequences such as RpShaanxi2011, Guangxi GX2013 and two sequences from Zhejiang Province (CoVZXC21/CoVZC45), as previously shown22,25, have strong phylogenetic recombination signals because they fall on different evolutionary lineages (with bootstrap support >80%) depending on what region of the genome is being examined.
Despite the high frequency of recombination among bat viruses, the block-like nature of the recombination patterns across the genome permits retrieval of a clean subalignment for phylogenetic analysis. Conservatively, we combined the three BFRs >2 kb identified above into non-recombining region 1 (NRR1). Removal of five sequences that appear to be recombinants and two small subregions of BFR A was necessary to ensure that there were no phylogenetic incongruence signals among or within the three BFRs. Alternatively, combining 3SEQ-inferred breakpoints, GARD-inferred breakpoints and the necessity of PI signals for inferring recombination, we can use the 9.9-kb region spanning nucleotides 11,885–21,753 (NRR2) as a putative non-recombining region; this approach is breakpoint-conservative because it is conservative in identifying breakpoints but not conservative in identifying non-recombining regions. Using a third consensus-based approach for identifying recombinant regions in individual sequences—with six different recombination detection methods in RDP5 (ref. 36)—gives a putative recombination-free alignment that we call non-recombinant alignment 3 (NRA3) (see Methods).
All three approaches to removal of recombinant genomic segments point to a single ancestral lineage for SARS-CoV-2 and RaTG13. Two other bat viruses (CoVZXC21 and CoVZC45) from Zhejiang Province fall on this lineage as recombinants of the RaTG13/SARS-CoV-2 lineage and the clade of Hong Kong bat viruses sampled between 2005 and 2007 (Fig. 1c). Specifically, progenitors of the RaTG13/SARS-CoV-2 lineage appear to have recombined with the Hong Kong clade (with inferred breakpoints at 11.9 and 20.8 kb) to form the CoVZXC21/CoVZC45-lineage. Sibling lineages to RaTG13/SARS-CoV-2 include a pangolin sequence sampled in Guangdong Province in March 2019 and a clade of pangolin sequences from Guangxi Province sampled in 2017.
Because the SARS-CoV-2 S protein has been implicated in past recombination events or possibly convergent evolution12, we specifically investigated several subregions of the S protein—the N-terminal domain of S1, the C-terminal domain of S1, the variable-loop region of the C-terminal domain, and S2. The variable-loop region in SARS-CoV-2 shows closer identity to the 2019 pangolin coronavirus sequence than to the RaTG13 bat virus, supported by phylogenetic inference (Fig. 2). On first examination this would suggest that that SARS-CoV-2 is a recombinant of an ancestor of Pangolin-2019 and RaTG13, as proposed by others11,22. However, on closer inspection, the relative divergences in the phylogenetic tree (Fig. 2, bottom) show that SARS-CoV-2 is unlikely to have acquired the variable loop from an ancestor of Pangolin-2019 because these two sequences are approximately 10–15% divergent throughout the entire S protein (excluding the N-terminal domain). It is RaTG13 that is more divergent in the variable-loop region (Extended Data Fig. 1) and thus likely to be the product of recombination, acquiring a divergent variable loop from a hitherto unsampled bat sarbecovirus28. This is notable because the variable-loop region contains the six key contact residues in the RBD that give SARS-CoV-2 its ACE2-binding specificity27,37. These residues are also in the Pangolin Guangdong 2019 sequence. The most parsimonious explanation for these shared ACE2-specific residues is that they were present in the common ancestors of SARS-CoV-2, RaTG13 and Pangolin Guangdong 2019, and were lost through recombination in the lineage leading to RaTG13. This provides compelling support for the SARS-CoV-2 lineage being the consequence of a direct or nearly-direct zoonotic jump from bats, because the key ACE2-binding residues were present in viruses circulating in bats.
Ancestry in non-recombinant regions
Using the most conservative approach to identification of a non-recombinant genomic region (NRR1), SARS-CoV-2 forms a sister lineage with RaTG13, with genetically related cousin lineages of coronavirus sampled in pangolins in Guangdong and Guangxi provinces (Fig. 3). Given that these pangolin viruses are ancestral to the progenitor of the RaTG13/SARS-CoV-2 lineage, it is more likely that they are also acquiring viruses from bats. While pangolins could be acting as intermediate hosts for bat viruses to get into humans—they develop severe respiratory disease38 and commonly come into contact with people through trafficking—there is no evidence that pangolin infection is a requirement for bat viruses to cross into humans.
Phylogenies of subregions of NRR1 depict an appreciable degree of spatial structuring of the bat sarbecovirus population across different regions (Fig. 3). One geographic clade includes viruses from provinces in southern China (Guangxi, Yunnan, Guizhou and Guangdong), with its major sister clade consisting of viruses from provinces in northern China (Shanxi, Henan, Hebei and Jilin) as well as Hubei Province in central China and Shaanxi Province in northwestern China. Several of the recombinant sequences in these trees show that recombination events do occur across geographically divergent clades. The Sichuan (SC2018) virus appears to be a recombinant of northern/central and southern viruses, while the two Zhejiang viruses (CoVZXC21 and CoVZC45) appear to carry a recombinant region from southern or central China.
TMRCA for NRRs of SARS-CoV-2 lineage
To avoid artefacts due to recombination, we focused on NRR1 and NRR2 and the recombination-masked alignment NRA3 to infer time-measured evolutionary histories. Visual exploration using TempEst39 indicates that there is no evidence for temporal signal in these datasets (Extended Data Fig. 2). This is not surprising for diverse viral populations with relatively deep evolutionary histories. In such cases, even moderate rate variation among long, deep phylogenetic branches will substantially impact expected root-to-tip divergences over a sampling time range that represents only a small fraction of the evolutionary history40. However, formal testing using marginal likelihood estimation41 does provide some evidence of a temporal signal, albeit with limited log Bayes factor support of 3 (NRR1), 10 (NRR2) and 3 (NRA3); see Supplementary Table 1.
In the absence of a strong temporal signal, we sought to identify a suitable prior rate distribution to calibrate the time-measured trees by examining several coronaviruses sampled over time, including HCoV-OC43, MERS-CoV, and SARS-CoV virus genomes. These datasets were subjected to the same recombination masking approach as NRA3 and were characterized by a strong temporal signal (Fig. 4), but also by markedly different evolutionary rates. Specifically, using a formal Bayesian approach42 (see Methods), we estimate a fast evolutionary rate (0.00169 substitutions per site yr–1, 95% highest posterior density (HPD) interval (0.00131,0.00205)) for SARS viruses sampled over a limited timescale (1 year), a slower rate (0.00078 (0.00063,0.00092) substitutions per site yr–1) for MERS-CoV on a timescale of about 4 years and the slowest rate (0.00024 (0.00019,0.00029) substitutions per site yr–1) for HCoV-OC43 over almost five decades. These differences reflect the fact that rate estimates can vary considerably with the timescale of measurement, a frequently observed phenomenon in viruses known as time-dependent evolutionary rates41,43,44. Over relatively shallow timescales, such differences can primarily be explained by varying selective pressure, with mildly deleterious variants being eliminated more strongly by purifying selection over longer timescales44,45,46. Consistent with this, we estimate a concomitantly decreasing non-synonymous-to-synonymous substitution rate ratio over longer evolutionary timescales: 1.41 (1.20,1.68), 0.35 (0.30,0.41) and 0.133 (0.129,0.136) for SARS, MERS-CoV and HCoV-OC43, respectively. In light of these time-dependent evolutionary rate dynamics, a slower rate is appropriate for calibration of the sarbecovirus evolutionary history. We compare both MERS-CoV- and HCoV-OC43-centred prior distributions (Extended Data Fig. 3) to examine the sensitivity of date estimates to this prior specification.
We infer time-measured evolutionary histories using a Bayesian phylogenetic approach while incorporating rate priors based on mean MERS-CoV and HCoV-OC43 rates and with standard deviations that allow for more uncertainty than the empirical estimates for both viruses (see Methods). Using both prior distributions, this results in six highly similar posterior rate estimates for NRR1, NRR2 and NRA3, centred around 0.00055 substitutions per site yr–1. The fact that these estimates lie between the rates for MERS-CoV and HCoV-OC43 is consistent with the intermediate sampling time range of about 18 years (Fig. 5). The consistency of the posterior rates for the different prior means also implies that the data do contribute to the evolutionary rate estimate, despite the fact that a temporal signal was visually not apparent (Extended Data Fig. 2). Below, we report divergence time estimates based on the HCoV-OC43-centred rate prior for NRR1, NRR2 and NRA3 and summarize corresponding estimates for the MERS-CoV-centred rate priors in Extended Data Fig. 4. Divergence time estimates based on the HCoV-OC43-centred rate prior for the separate BFRs (Supplementary Table 3) show consistency in TMRCA estimates across the genome.
The divergence time estimates for SARS-CoV-2 and SARS-CoV from their respective most closely related bat lineages are reasonably consistent among the three approaches we use to eliminate the effects of recombination in the alignment. Using the most conservative approach (NRR1), the divergence time estimate for SARS-CoV-2 and RaTG13 is 1969 (95% HPD: 1930–2000), while that between SARS-CoV and its most closely related bat sequence is 1962 (95% HPD: 1932–1988); see Fig. 5. These are in general agreement with estimates using NRR2 and NRA3, which result in divergence times of 1982 (1948–2009) and 1948 (1879–1999), respectively, for SARS-CoV-2, and estimates of 1952 (1906–1989) and 1970 (1932–1996), respectively, for the divergence time of SARS-CoV from its closest known bat relative. The SARS-CoV divergence times are somewhat earlier than dates previously estimated15 because previous estimates were obtained using a collection of SARS-CoV genomes from human and civet hosts (as well as a few closely related bat genomes), which implies that evolutionary rates were predominantly informed by the short-term SARS outbreak scale and probably biased upwards. Indeed, the rates reported by these studies are in line with the short-term SARS rates that we estimate (Fig. 4). The estimated divergence times for the pangolin virus most closely related to the SARS-CoV-2/RaTG13 lineage range from 1851 (1730–1958) to 1877 (1746–1986), indicating that these pangolin lineages were acquired from bat viruses divergent to those that gave rise to SARS-CoV-2. Current sampling of pangolins does not implicate them as an intermediate host.
Identifying the origins of an emerging pathogen can be critical during the early stages of an outbreak, because it may allow for containment measures to be precisely targeted at a stage when the number of daily new infections is still low. Early detection via genomics was not possible during Southeast Asia’s initial outbreaks of avian influenza H5N1 (1997 and 2003–2004) or the first SARS outbreak (2002–2003). By 2009, however, rapid genomic analysis had become a routine component of outbreak response. The 2009 influenza pandemic and subsequent outbreaks of MERS-CoV (2012), H7N9 avian influenza (2013), Ebola virus (2014) and Zika virus (2015) were met with rapid sequencing and genomic characterization. For the current pandemic, the ‘novel pathogen identification’ component of outbreak response delivered on its promise, with viral identification and rapid genomic analysis providing a genome sequence and confirmation, within weeks, that the December 2019 outbreak first detected in Wuhan, China was caused by a coronavirus3. Unfortunately, a response that would achieve containment was not possible. Given what was known about the origins of SARS, as well as identification of SARS-like viruses circulating in bats that had binding sites adapted to human receptors29,30,31, appropriate measures should have been in place for immediate control of outbreaks of novel coronaviruses. The key to successful surveillance is knowing which viruses to look for and prioritizing those that can readily infect humans47.
The difficulty in inferring reliable evolutionary histories for coronaviruses is that their high recombination rate48,49 violates the assumption of standard phylogenetic approaches because different parts of the genome have different histories. To begin characterizing any ancestral relationships for SARS-CoV-2, NRRs of the genome must be identified so that reliable phylogenetic reconstruction and dating can be performed. Evolutionary rate estimation can be profoundly affected by the presence of recombination50. Because there is no single accepted method of inferring breakpoints and identifying clean subregions with high certainty, we implemented several approaches to identifying three classic statistical signals of recombination: mosaicism, phylogenetic incongruence and excessive homoplasy51. Our most conservative approach attempted to ensure that putative NRRs had no mosaic or phylogenetic incongruence signals. A second breakpoint-conservative approach was conservative with respect to breakpoint identification, but this means that it is accepting of false-negative outcomes in breakpoint inference, resulting in less certainty that a putative NRR truly contains no breakpoints. A third approach attempted to minimize the number of regions removed while also minimizing signals of mosaicism and homoplasy. The origins we present in Fig. 5 (NRR1) are conservative in the sense that NRR1 is more likely to be non-recombinant than NRR2 or NRA3. Because the estimated rates and divergence dates were highly similar in the three datasets analysed, we conclude that our estimates are robust to the method of identifying a genome’s NRRs.
Due to the absence of temporal signal in the sarbecovirus datasets, we used informative prior distributions on the evolutionary rate to estimate divergence dates. Calibration of priors can be performed using other coronaviruses (SARS-CoV, MERS-CoV and HCoV-OC43), but estimated rates vary with the timescale of sample collection. In the presence of time-dependent rate variation, a widely observed phenomenon for viruses43,44,52, slower prior rates appear more appropriate for sarbecoviruses that currently encompass a sampling time range of about 18 years. Our approach resulted in similar posterior rates using two different prior means, implying that the sarbecovirus data do inform the rate estimate even though a root-to-tip temporal signal was not apparent.
The relatively fast evolutionary rate means that it is most appropriate to estimate shallow nodes in the sarbecovirus evolutionary history. Accurate estimation of ages for deeper nodes would require adequate accommodation of time-dependent rate variation. While such models have recently been made available, we lack the information to calibrate the rate decline over time (for example, through internal node calibrations44). As a proxy, it would be possible to model the long-term purifying selection dynamics as a major source of time-dependent rates43,44,52, but this is beyond the scope of the current study. The assumption of long-term purifying selection would imply that coronaviruses are in endemic equilibrium with their natural host species, horseshoe bats, to which they are presumably well adapted. While there is evidence of positive selection in the sarbecovirus lineage leading to RaTG13/SARS-CoV-2 (ref. 53), this is inferred to have occurred before the divergence of RaTG13 and SARS-CoV-2 and thus should not influence our inferences.
Of importance for future spillover events is the appreciation that SARS-CoV-2 has emerged from the same horseshoe bat subgenus that harbours SARS-like coronaviruses. Another similarity between SARS-CoV and SARS-CoV-2 is their divergence time (40–70 years ago) from currently known extant bat virus lineages (Fig. 5). This long divergence period suggests there are unsampled virus lineages circulating in horseshoe bats that have zoonotic potential due to the ancestral position of the human-adapted contact residues in the SARS-CoV-2 RBD. Without better sampling, however, it is impossible to estimate whether or how many of these additional lineages exist. While there is involvement of other mammalian species—specifically pangolins for SARS-CoV-2—as a plausible conduit for transmission to humans, there is no evidence that pangolins are facilitating adaptation to humans. A hypothesis of snakes as intermediate hosts of SARS-CoV-2 was posited during the early epidemic phase54, but we found no evidence of this55,56; see Extended Data Fig. 5.
With horseshoe bats currently the most plausible origin of SARS-CoV-2, it is important to consider that sarbecoviruses circulate in a variety of horseshoe bat species with widely overlapping species ranges57. Nevertheless, the viral population is largely spatially structured according to provinces in the south and southeast on one lineage, and provinces in the centre, east and northeast on another (Fig. 3). This boundary appears to be rarely crossed. Two exceptions can be seen in the relatively close relationship of Hong Kong viruses to those from Zhejiang Province (with two of the latter, CoVZC45 and CoVZXC21, identified as recombinants) and a recombinant virus from Sichuan for which part of the genome (region B of SC2018 in Fig. 3) clusters with viruses from provinces in the centre, east and northeast of China. SARS-CoV-2 and RaTG13 are also exceptions because they were sampled from Hubei and Yunnan, respectively. The fact that they are geographically relatively distant is in agreement with their somewhat distant TMRCA, because the spatial structure suggests that migration between their locations may be uncommon. From this perspective, it may be useful to perform surveillance for more closely related viruses to SARS-CoV-2 along the gradient from Yunnan to Hubei.
It is clear from our analysis that viruses closely related to SARS-CoV-2 have been circulating in horseshoe bats for many decades. The unsampled diversity descended from the SARS-CoV-2/RaTG13 common ancestor forms a clade of bat sarbecoviruses with generalist properties—with respect to their ability to infect a range of mammalian cells—that facilitated its jump to humans and may do so again. Although the human ACE2-compatible RBD was very likely to have been present in a bat sarbecovirus lineage that ultimately led to SARS-CoV-2, this RBD sequence has hitherto been found in only a few pangolin viruses. Furthermore, the other key feature thought to be instrumental in the ability of SARS-CoV-2 to infect humans—a polybasic cleavage site insertion in the S protein—has not yet been seen in another close bat relative of the SARS-CoV-2 virus.
The existing diversity and dynamic process of recombination amongst lineages in the bat reservoir demonstrate how difficult it will be to identify viruses with potential to cause major human outbreaks before they emerge. This underscores the need for a global network of real-time human disease surveillance systems, such as that which identified the unusual cluster of pneumonia in Wuhan in December 2019, with the capacity to rapidly deploy genomic tools and functional studies for pathogen identification and characterization.
Complete genome sequence data were downloaded from GenBank and ViPR; accession numbers of all 68 sequences are available in Supplementary Table 4. Sequences were aligned by MAFTT58 v.7.310, with a final alignment length of 30,927, and used in the analyses below.
We compiled a dataset including 27 human coronavirus OC43 virus genomes and ten related animal virus genomes (six bovine, three white-tailed deer and one canine virus). The canine viral genome was excluded from the Bayesian phylogenetic analyses because temporal signal analyses (see below) indicated that it was an outlier.
We extracted a similar number (n = 35) of genomes from a MERS-CoV dataset analysed by Dudas et al.59 using the phylogenetic diversity analyser tool60 (v.0.5).
We compiled a set of 69 SARS-CoV genomes including 58 sampled from humans and 11 sampled from civets and raccoon dogs. This dataset comprises an updated version of that used in Hon et al.15 and includes a cluster of genomes sampled in late 2003 and early 2004, but the evolutionary rate estimate without this cluster (0.00175 substitutions per site yr–1 (0.00117,0.00229)) is consistent with the complete dataset (0.00169 substitutions per site yr–1, (0.00131,0.00205)).
Sarbecovirus, HCoV-OC43 and SARS-CoV data were assembled from GenBank to be as complete as possible, with sampling year as an inclusion criterion. MERS-CoV data were subsampled to match sample sizes with SARS-CoV and HCoV-OC43.
Because coronaviruses are known to be highly recombinant, we used three different approaches to identify non-recombinant regions for use in our Bayesian time-calibrated phylogenetic inference.
First, we took an approach that relies on identification of mosaic regions (via 3SEQ14 v.1.7) that are also supported by PI signals19. Because 3SEQ is the most statistically powerful of the mosaic methods61, we used it to identify the best-supported breakpoint history for each potential child (recombinant) sequence in the dataset. A single 3SEQ run on the genome alignment resulted in 67 out of 68 sequences supporting some recombination in the past, with multiple candidate breakpoint ranges listed for each putative recombinant. Next, we (1) collected all breakpoints into a single set, (2) complemented this set to generate a set of non-breakpoints, (3) grouped non-breakpoints into contiguous BFRs and (4) sorted these regions by length. A phylogenetic tree—using RAxML v8.2.8 (ref. 62,63), the GTR + Γ model and 100 bootstrap replicates—was inferred for each BFR >500 nt.
We considered (1) the possibility that BFRs could be combined into larger non-recombinant regions and (2) the possibility of further recombination within each BFR.
We named the length-sorted BFRs as: BFR A (nt positions 13,291–19,628, length = 6,338 nt), BFR B (nt positions 3,625–9,150, length = 5,526 nt), BFR C (nt positions 9,261–11,795, length = 2,535 nt), BFR D (nt positions 27,702–28,843, length = 1,142 nt) and six further regions (E–J). Phylogenetic trees and exact breakpoints for all ten BFRs are shown in Supplementary Figs. 1–10. Regions A–C had similar phylogenetic relationships among the southern China bat viruses (Yunnan, Guangxi and Guizhou provinces), the Hong Kong viruses, northern Chinese viruses (Jilin, Shanxi, Hebei and Henan provinces, including Shaanxi), pangolin viruses and the SARS-CoV-2 lineage. Because these subclades had different phylogenetic relationships in region D (Supplementary Fig. 4), that region and shorter BFRs were not included in combined putative non-recombinant regions.
Regions A–C were further examined for mosaic signals by 3SEQ, and all showed signs of mosaicism. In region A, we removed subregion A1 (nt positions 3,872–4,716 within region A) and subregion A4 (nt 1,642–2,113) because both showed PI signals with other subregions of region A. After removal of A1 and A4, we named the new region A′. In addition, sequences NC_014470 (Bulgaria 2008), CoVZXC21, CoVZC45 and DQ412042 (Hubei-Yichang) needed to be removed to maintain a clean non-recombinant signal in A′. Region B showed no PI signals within the region, except one including sequence SC2018 (Sichuan), and thus this sequence was also removed from the set. Region C showed no PI signals within it. Combining regions A′, B and C and removing the five named sequences gives us putative NRR1, as an alignment of 63 sequences. We say that this approach is conservative because sequences and subregions generating recombination signals have been removed, and BFRs were concatenated only when no PI signals could be detected between them. The construction of NRR1 is the most conservative as it is least likely to contain any remaining recombination signals.
In our second stage, we wanted to construct non-recombinant regions where our approach to breakpoint identification was as conservative as possible. We call this approach breakpoint-conservative, but note that this has the opposite effect to the construction of NRR1 in that this approach is the most likely to allow breakpoints to remain inside putative non-recombining regions. In other words, a true breakpoint is less likely to be called as such (this is breakpoint-conservative), and thus the construction of a non-recombining region may contain true recombination breakpoints (with insufficient evidence to call them as such). In this approach, we considered a breakpoint as supported only if it had three types of statistical support: from (1) mosaic signals identified by 3SEQ, (2) PI signals identified by building trees around 3SEQ’s breakpoints and (3) the GARD algorithm35, which identifies breakpoints by identifying PI signals across proposed breakpoints. Because 3SEQ identified ten BFRs >500 nt, we used GARD’s (v.2.5.0) inference on 10, 11 and 12 breakpoints. A reduced sequence set of 25 sequences chosen to capture the breadth of diversity in the sarbecoviruses (obvious recombinants not involving the SARS-CoV-2 lineage were also excluded) was used because GARD is computationally intensive. GARD identified eight breakpoints that were also within 50 nt of those identified by 3SEQ. PI signals were identified (with bootstrap support >80%) for seven of these eight breakpoints: positions 1,684, 3,046, 9,237, 11,885, 21,753, 22,773 and 24,628. Using these breakpoints, the longest putative non-recombining segment (nt 1,885–21,753) is 9.9 kb long, and we call this region NRR2.
Our third approach involved identifying breakpoints and masking minor recombinant regions (with gaps, which are treated as unobserved characters in probabilistic phylogenetic approaches). Specifically, we used a combination of six methods implemented in v.5.5 of RDP5 (ref. 36) (RDP, GENECONV, MaxChi, Bootscan, SisScan and 3SEQ) and considered recombination signals detected by more than two methods for breakpoint identification. Except for specifying that sequences are linear, all settings were kept to their defaults. Based on the identified breakpoints in each genome, only the major non-recombinant region is kept in each genome while other regions are masked. To evaluate the performance procedure, we confirmed that the recombination masking resulted in (1) a markedly different outcome of the PHI test64, (2) removal of well-supported (bootstrap value >95%) incompatible splits in Neighbor-Net65 and (3) a near-complete reduction of mosaic signal as identified by 3SEQ. If the latter still identified non-negligible recombination signal, we removed additional genomes that were identified as major contributors to the remaining signal. This produced non-recombining alignment NRA3, which included 63 of the 68 genomes.
Bayesian divergence time estimation
We focused on these three non-recombining regions/alignments for divergence time estimation; this avoids inappropriate modelling of evolutionary processes with recombination on strictly bifurcating trees, which can result in different artefacts such as homoplasies that inflate branch lengths and lead to apparently longer evolutionary divergence times. To examine temporal signal in the sequenced data, we plotted root-to-tip divergence against sampling time using TempEst39 v.1.5.3 based on a maximum likelihood tree. The latter was reconstructed using IQTREE66 v.2.0 under a general time-reversible (GTR) model with a discrete gamma distribution to model inter-site rate variation.
Time-measured phylogenetic reconstruction was performed using a Bayesian approach implemented in BEAST42 v.1.10.4. When the genomic data included both coding and non-coding regions we used a single GTR + Γ substitution model; for concatenated coding genes we partitioned the alignment by codon position and specified an independent GTR + Γ model for each partition with a separate gamma model to accommodate inter-site rate variation. We used an uncorrelated relaxed clock model with log-normal distribution for all datasets, except for the low-diversity SARS data for which we specified a strict molecular clock model. For the HCoV-OC43, MERS-CoV and SARS datasets we specified flexible skygrid coalescent tree priors. In the absence of any reasonable prior knowledge on the TMRCA of the sarbecovirus datasets (which is required for grid specification in a skygrid model), we specified a simpler constant size population prior. As informative rate priors for the analysis of the sarbecovirus datasets, we used two different normal prior distributions: one with a mean of 0.00078 and s.d. = 0.00075 and one with a mean of 0.00024 and s.d. = 0.00025. These means are based on the mean rates estimated for MERS-CoV and HCoV-OC43, respectively, while the standard deviations are set ten times higher than empirical values to allow greater prior uncertainty and avoid strong bias (Extended Data Fig. 3). In our analyses of the sarbecovirus datasets, we incorporated the uncertainty of the sampling dates when exact dates were not available. To estimate non-synonymous over synonymous rate ratios for the concatenated coding genes, we used the empirical Bayes Renaissance counting’procedure67. Temporal signal was tested using a recently developed marginal likelihood estimation procedure41 (Supplementary Table 1).
Posterior distributions were approximated through Markov chain Monte Carlo sampling, which were run sufficiently long to ensure effective sampling sizes >100. BEAST inferences made use of the BEAGLE v.3 library68 for efficient likelihood computations. We used TreeAnnotator to summarize posterior tree distributions and annotated the estimated values to a maximum clade credibility tree, which was visualized using FigTree.
Further information on research design is available in the Nature Research Reporting Summary linked to this article.
All custom code used in the manuscript is available at https://github.com/plemey/SARSCoV2origins.
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We thank all authors who have kindly deposited and shared genome data on GISAID. We thank T. Bedford for providing M.F.B. with an alignment on which an initial recombination analysis was done. We thank A. Chan and A. Irving for helpful comments on the manuscript. The research leading to these results received funding (to A.R. and P.L.) from the European Research Council under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 725422-ReservoirDOCS). D.L.R. is funded by the MRC (no. MC_UU_1201412). The Artic Network receives funding from the Wellcome Trust through project no. 206298/Z/17/Z. P.L. acknowledges support by the Research Foundation—Flanders (‘Fonds voor Wetenschappelijk Onderzoek—Vlaanderen’ (nos. G066215N, G0D5117N and G0B9317N)) and by the European Union’s Horizon 2020 project MOOD (no. 874850). T.L. is funded by The National Natural Science Foundation of China Excellent Young Scientists Fund (Hong Kong and Macau; no. 31922087). We thank originating laboratories at South China Agricultural University (Y. Shen, L. Xiao and W. Chen; no. EPI_ISL_410721) and Beijing Institute of Microbiology and Epidemiology (W.-C. Cao, T.T.-Y.L., N. Jia, Y.-W. Zhang, J.-F. Jiang and B.-G. Jiang, nos. EPI_ISL_410538, EPI_ISL_410539, EPI_ISL_410540, EPI_ISL_410541 and EPI_ISL_410542) for the use of sequence data via the GISAID platform.
The authors declare no competing interests.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Extended Data Fig. 1 Phylogenetic relationships in the C-terminal domain (CTD).
Posterior means (horizontal bars) of patristic distances between SARS-CoV-2 and its closest bat and pangolin sequences, for the spike protein’s variable loop region and CTD region excluding the variable loop. Boxes show 95% HPD credible intervals. Means and 95% HPD intervals are 0.080 [0.058–0.101] and 0.530 [0.304–0.780] for the patristic distances between SARS-CoV-2 and RaTG13 (green) and 0.143 [0.109–0.180] and 0.154 [0.093–0.231] for the patristic distances between SARS-CoV-2 and Pangolin 2019 (orange). Gray inset shows majority rule consensus trees with mean posterior branch lengths for the two regions, with posterior probabilities on the key nodes showing the relationships among SARS-CoV-2, RaTG13, and Pangolin 2019.
Extended Data Fig. 2 Lack of root-to-tip temporal signal in SARS-CoV-2.
Root-to-tip divergence as a function of sampling time for non-recombinant regions NRR1 and NRR2 and recombination-masked alignment set NRA3. The plots are based on maximum likelihood tree reconstructions with a root position that maximises the residual mean squared for the regression of root-to-tip divergence and sampling time.
Extended Data Fig. 3 Priors and posteriors for evolutionary rate of SARS-CoV-2.
Posterior rate distributions for MERS-CoV (far left) and HCoV-OC43 (far right) using BEAST on n = 27 sequences spread over 4 years (MERS-CoV) and n = 27 sequences spread over 49 years (HCoV-OC43). As illustrated by the dashed arrows, these two posteriors motivate our specification of prior distributions with standard deviations inflated 10-fold (light color). These rate priors are subsequently used in the Bayesian inference of posterior rates for NRR1, NRR2, and NRA3 as indicated by the solid arrows.
Extended Data Fig. 4 TMRCAs for SARS-CoV and SARS-CoV-2.
Divergence time estimates based on the three regions/alignments where the effects of recombination have been removed. The red and blue boxplots represent the divergence time estimates for SARS-CoV-2 (red) and the 2002-2003 SARS-CoV (blue) from their most closely related bat virus, with the light- and dark-colored versions based on the HCoV-OC43 and MERS-CoV centered priors, respectively. Green boxplots show the TMRCA estimate for the RaTG13/SARS-CoV-2 lineage and its most closely related pangolin lineage (Guangdong 2019), with the light and dark coloured version based on the HCoV-OC43 and MERS-CoV centred priors, respectively. TMRCA estimates for SARS-CoV-2 and SARS-CoV from their respective most closely related bat lineages are reasonably consistent for the different data sets and different rate priors in our analyses. Posterior means with 95% HPDs are shown in Supplementary Information Table 2.
Extended Data Fig. 5 Comparisons of GC content across taxa.
Conducting analogous analyses of codon usage bias as Ji et al. (2020) with additional (and higher quality) snake coding sequence data and several miscellaneous eukaryotes with low genomic GC content failed to find any meaningful clustering of the SARS-CoV-2 with snake genomes (a). Instead, similarity in codon usage metrics between the SARS-CoV-2 and eukaryotes analyzed was correlated with coding sequence GC content of the eukaryote, with more similar codon usage being identified in eukaryotes with low GC content similar to that of the coronavirus (b).
Supplementary Tables 1–3 and Figs. 1–10.
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Boni, M.F., Lemey, P., Jiang, X. et al. Evolutionary origins of the SARS-CoV-2 sarbecovirus lineage responsible for the COVID-19 pandemic. Nat Microbiol 5, 1408–1417 (2020). https://doi.org/10.1038/s41564-020-0771-4
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International Legal Rights of the Jewish People and the State of Israel
In international law, as in all law, there are always two sides to a question. If this were not the case, there would be little need for legal solutions. Moreover, both parties in any conflict believe the right is on their side, or at least that they have means to prove this to be so. Accordingly, no law is ever created in a vacuum; a law is created when a serious enough need arises. In 1917, owing to the events of World War I, a serious need was identified and a voice was raised. The need was that of the Jewish people, dispersed across the earth for some two thousand years, to have a national home. The voice was that of Lord Balfour, speaking on behalf of the British War Cabinet in defense of the Jewish people worldwide. This compelling need found official expression in the Balfour Declaration of 1917. The Balfour Declaration was a political statement with no legal authority; moreover, it was not international. Nonetheless it was a major turning point in the history of the dispersed Jewish people, giving them a future hope of eventually fulfilling their never dying longing for their ancient Holy Land. What it accomplished was to raise the profile, internationally, of the need of a stateless people to have a “national home” to which they could return. Of monumental significance was the official recognition of the all-important historic, religious and cultural links of the Jews to the land of their forefathers, the land that had come to be known under the Greeks and Romans as “Palestine”. Because the cause was just and the concept justified, there needed to be a way to elevate the content of this Declaration to the level of international law. Accordingly, the matter was taken up by the Supreme Council of the Principal Allied and Associated Powers (Britain, France, Italy, Japan and the United States) at the Paris Peace Conference in 1919 (there was also the Faisal Weizmann Agreement of January 1919 - which stipulated that all of Palestine as historically maped is the territory of the Jewish people). The issue became more complex as submissions for territorial claims were presented by both Arab and Jewish delegations, as the old Ottoman Empire was being apportioned out to the victorious Powers; thus the matter was not able to be settled within the time frame of the Paris Conference. What did happen at the Paris Conference that factored into the progression of events we are considering here was the establishment of the League of Nations which, in Article 22 of its Covenant, provided for the setting up of a mandate system as a trust for the Old Ottoman territories. The next important milestone on the road to international legal status and a Jewish national home was the San Remo Conference, held at Villa Devachan in San Remo, Italy, from 18 to 26 April 1920. This was an ‘extension’ of the Paris Peace Conference of 1919 for the purpose of dealing with some of these outstanding issues. The aim of the four (out of five) members of the Supreme Council of the Principal Allied and Associated Powers that met in San Remo (the United States being present as observer only, owing to the new noninterventionist policy of President Woodrow Wilson), was to consider the earlier submissions of the claimants, to deliberate and to make decisions on the legal recognition of each claim. The outcome, relying on Article 22 of the Covenant of the League of Nations, was the setting up of (3) three mandates, one over Syria and Lebanon (later separated into two mandates), one over Mesopotamia (Iraq), and one over Palestine.
The Mandate for Palestine was entrusted to Great Britain, as a “sacred trust of civilization” in respect of “the establishment in all of Palestine of a National Home for the Jewish people”.
This was a binding resolution with all the force of international law.
In two out of the original three Mandates, it was recognized that the indigenous people had the capacity to govern themselves, with the Mandatory Power merely assisting in the establishment of the institutions of government, where necessary. This was not true of Palestine, as Palestine was, under the Mandate, to become a homeland (“national home”) for the Jewish people. Although the Jewish people were part of the indigenous population of Palestine, the majority of them at that time were not living in the Land. The Mandate for Palestine was thus quite different from the others and set out how the Land was to be settled by Jews in preparation for their forming a viable nation in the territory then known as “Palestine”. The unique obligations of the Mandatory to the Jewish people in respect of the establishment of their national home in all of Palestine thus gave a sui generis (unique, one of a kind) character to the Mandate for Palestine.
The boundaries of the “Palestine” referred to in the claimants’ submissions included territories west and east of the Jordan River.
The submissions of the Jewish claimants specified that the ultimate purpose of the mandate would be the “creation of an autonomous commonwealth”, provided “that nothing must be done that might prejudice the civil and religious rights of the non-Jewish communities at present established in Palestine”. The resulting Mandate for Palestine, approved by the Council of the League of Nations in July 1922, was an international treaty and, as such, was legally binding. The decision made in San Remo was a watershed moment in the history of the Jewish people who had been a people without a home for some two thousand years. From the perspective of Chaim Weizmann, president of the newly formed Zionist Organization and later to become the first President of the State of Israel, “recognition of our rights in Palestine is embodied in the treaty with Turkey, and has become part of international law. This is the most momentous political event in the whole history of our movement, and it is, perhaps, no exaggeration to say in the whole history of our people since the Exile.” To the Zionist Organization of America, the San Remo Resolution “crowns the British [Balfour] declaration by enacting it as part of the law of nations of the world.” The policy to be given effect in the Mandate for Palestine was consistent with the Balfour Declaration, in significantly recognizing the historic, cultural and religious ties of the Jewish people to the Holy Land, and even stronger than the Declaration through the insertion of the fundamental principle that Palestine should be reconstituted as the national home of the Jewish people. It is particularly relevant to underline the inclusion in the terms of the Mandate (through Article 2) of the fundamental principle set out in the Preamble of this international agreement that “recognition has thereby been given to the historical connection of the Jewish people with Palestine and to the grounds for reconstituting their national home in that country”. The primary objective of the Mandate was to provide a national home for the Jewish people—including Jewish people dispersed worldwide—in their ancestral home.
The Arab people, who already exercised sovereignty in a number of States, were guaranteed protection of their civil and religious rights under the Mandate as long as they wished to remain, even after the State of Israel was ultimately formed in 1948. Moreover, a new State; Trans-Jordan was meanwhile added as a territory under Arab sovereignty, carved out of the very mandated territory allocated to the Jewish people at issue, by the British, prior to the actual signing of the Mandate in 1922 (see below). When the Council of the League of Nations approved the Mandate for Palestine in July 1922, it became binding on all 51 Members of the League.
This act of the League enabled the ultimate realization of the long cherished dream of the restoration of the Jewish people to their ancient land and validated the existence of historical facts and events linking the Jewish people to Palestine. For the Supreme Council of the Principal Allied Powers, and for the Council of the League of Nations, these historical facts were considered to be accepted and established.
In the words of Neville Barbour, “In 1922, international sanction was given to the Balfour Declaration by the issue of the Palestine Mandate”. The rights granted to the Jewish people in the Mandate for Palestine were to be given effect in all of Palestine. It thus follows that the legal rights of the claimants to sovereignty over the Old City of Jerusalem similarly derive from the decisions of the Supreme Council of the Principal Allied Powers in San Remo and from the terms of the Mandate for Palestine approved by the Council of the League of Nations.
In March 1921, in Cairo, Great Britain decided to partition the mandated territory of Palestine, for international political reasons of its own. Article 25 of the Mandate gave the Mandatory Power permission to postpone or withhold most of the terms of the Mandate in the area of land east of the Jordan River (“Trans-Jordan”). Great Britain, as Mandatory Power, exercised that right. For former UN Ambassador, Professor Yehuda Zvi Blum, the rights vested in the Arab people of Palestine with respect to the principle of self-determination were fulfilled as a result of this initial partition of Palestine approved by the Council of the League of Nations in 1922. According to Professor Blum: “The Palestinian Arabs have long enjoyed self-determination in their own state – the Palestinian Arab State of Jordan”. (Worth mentioning here, in a letter apparently written on 17 January 1921 to Churchill’s Private Secretary, Col. T.E. Lawrence (“of Arabia”) had reported that, in return for Arab sovereignty in Iraq, Trans-Jordan and Syria, King Hussein’s eldest son, Emir Feisal—a man said by Lawrence to be known for keeping his word—had “agreed to abandon all claims of his father to Palestine”.) After this partition, Churchill—British Colonial Secretary at the time— immediately reaffirmed the commitment of Great Britain to give effect to the policies of the Balfour Declaration in all the other parts of the territory covered by the Mandate for Palestine west of the Jordan River.
This pledge included the area of Jerusalem and its OldCity. In Churchill’s own words: “It is manifestly right that the Jews who are scattered all over the world should have a national centre and a national home where some of them may be reunited. And where else could that be but in the land of Palestine, with which for more than three thousand years they have been intimately and profoundly associated?” Thus, in a word, the primary foundations in international law for the “legal” claim based on “historic rights” or “historic title” of the Jewish people in respect of Palestine are the San Remo decisions of April 1920, the Mandate for Palestine of July 1922, approved by the Council of the League of Nations and bearing the signatures of those same Principal Allied Powers but rendering it an international treaty binding on all Member States, and the Covenant of the League of Nations itself (Art. 22).
Re: Israel – To whom it may concern in Europe, Asia, Far East, the US and elsewhere:
We are tired of hearing that withdrawal from Judea and Samaria will bring peace. We know and you know that it would bring another Gaza. So stop saying it and promoting this fallacy. Past experience has proven that concessions, appeasement and land for peace only increased terror, violence and more conflict and hostilities.
We are tired of hearing that land beyond the Green Line is ‘Arab-Palestinian land’. The Green Line is simply an armistice line that has no political significance. You know this too. The San Remo Treaty of 1920 Granted the Mandate for Palestine to the Jewish people, the same Allied powers also established 21 Arab States and one Jewish State – The Arabs are not willing to give up any part of the 21 Arab States and the Jews are not willing to give up any part of the Jewish State.
We are tired of hearing about the “Arab-Palestinian people.” They are no different from the Arabs of Syria or Egypt, from which most of their ancestors migrated in the last 150 years or so. There is no Arab-Palestinian language or religion, and until very recently they considered themselves simply ‘Arabs’. Their culture is almost entirely defined by their opposition to the Jewish State. Teaching hate, violence and terror to their children. There never was an Arab-Palestinian State or people in History. The Arab Palestinians have a State in Jordan which is 80% of the land originally allocated to the Jewish people under the San Remo Treaty of 1920 and in violation of the 1919 Faisal Weizmann Agreement.
We are tired of hearing that “the Arab-Palestinians deserve a state.” We are indigenous here, not them, and their behavior entitles them more to a trial at The Hague than to a State. The Arab- Palestinians have a State it is called Jordan which was carved out of Jewish allocated land in 1922, in violation of the treaty of 1920.
And they certainly don’t deserve our Jewish State, which is the only State they want. They already took 80% of Jewish allocated land which is Jordan, a country that never existed in history before WWI. Israel also gave them the Gaza Strip which became a terrorist entity.
We are tired of hearing about ‘The Occupation’, it is "Liberated Jewish Land". As Minister Naftali Bennett said the other day, you can’t be an occupier in your own land. The Arabs are the occupiers, Greater Israel has been a Jewish State for 4,000 years even if it was temporarily conquered and occupied by various nations over the centuries.
We are tired of hearing that “settlements are illegal under international law.” They are not. The San Remo Treaty of 1920 explicitly stated that Jewish people can reside anywhere in the Mandate for Palestine, those terms have not been abrogated and are set in perpetuity.
We are tired of hearing that “settlement construction is an obstacle to peace.” Arab rejectionism, destruction, violence, terrorism and suicide bombing is the reason there is no peace. When the Arab-Palestinians teach and preach hate, terror and destruction to their children, this is definitely not a road to peace and coexistence.
By the way, we are pro-peace. We are just not pro-suicide and self destruction.
We are tired of hearing about the 5 million (or whatever ridiculous number there are alleged to be) ‘Arab-Palestinian refugees’ or the ‘Arab-Palestinian Diaspora’. There were about 600,000 Arabs that left their homes in 1948, mostly of their own volition, more or less at the same time as the over a million families Jewish refugees from Arab countries, of which the Arabs confiscated all their assets personal valueables, businesses, homes and land (120,000 sq. km. which is 6 times the size of Israel) and assets totaling trillions dollars. We resettled ours with limited land and resources — resettle yours (on the land and homes you confiscated from the Jewish people), the 21 Arab states have more land and resources. The Arab dis-information must be ignored and countered.
We are tired of hearing anything from anyone associated with the U.N. The U.N. is a parasitic and criminal enterprise dominated by our mortal enemies. The U.N. cannot create states, it can only recommend a non-binding resolution with no legal standing and so can other nations only recommend and not create a state that never existed before in history. If they want an Arab-Palestinian state, it already exists, it is Jordan which has taken 80% of Jewish allocated land. They also have the land the Arabs Countries confiscated from the Jewish people which is 6 times the size of Israel.
We are tired of stupid post-colonialist rhetoric. We are not ‘colonists’ and Arabs do not have the right to murder us in the name of ‘resistance’ or beheading Jewish Rabbi’s in Jerusalem’s Har Nof Synagogue. Talking this way reveals you as moral imbeciles. They train their children to be suicide bombers and terrorists. The Arabs are the colonialists, they have colonized the whole Middle East and they are taking over Europe.
You can not recognize a state and people that never existed and that has no borders, no single government, and no economy. They are not trusted by the Arab states either.
We know we can not depend on any kind of security guarantee from anyone except the Israel Defense Forces. So stop being insulted because we do not trust you. And do not ask us to give up any nuclear weapons we might or might not have or any other method and technology that could help protect us.
If you hate us so much, give us back all our Medical technology that saved your lives. Give us back all our technology development that helped you advance economically and the list goes on and on.
We know that the left-wing parties in Israel are bankrupt of ideas. We are not going to vote for them, no matter how much you would like us to. So do not bother trying to influence our election. We will only vote for a government that protects its people and cares about the Jewish heritage, more than it cares for world opinion.
Don’t believe what you read in Ha’aretz newspaper, they represent a minority that has no allegiance to the Jewish heritage.
Jerusalem, undivided, is the capital of the Jewish State of Israel. Get used to it, because you can’t change it, the Jewish temple will be rebuilt in Jerusalem. It was never a Capital of any other nation.
Ordinary Israelis who care about their heritage and ancestry.
The Arab-Palestinian state is in Jordan. The Arabs have no legal claim to any territory west of the Jordan river. Jordan's territory was taken away from the Jewish people and given to the Arabs as their state in violation of the San Remo Treaty of 1920. The Arabs can also move to the million Jewish homes the Arabs confiscated from the Jewish people who were expelled from the Arab countries.
The legal uncontested claim of Israel to the Jewish Land in the Mandate for Palestine.
When the U.N. passes a resolution it is only a recommendation. If accepted by the parties it becomes a valid agreement and or Treaty.
In the case of Israel and the Arabs, the U.N. passed a resolution in 1947 for the creation of a Jewish State and an Arab State. The Arabs did not accept the U.N. resolution of 1947 for a Jewish State and an Arab State. Thus the resolution is not binding. As such Israel's rights to the land falls back to the terms in the San Remo Treaty of 1920 which delineated The Mandate for Palestine to the Jewish people with all its terms without any deviation.
If anyone is contesting the legitimacy and sovereignty of the territorial boundaries assigned based on the San Remo Treaty of 1920 and the Treaty of Sevres of 1920 Article 95. You now have to contest and question the legitimacy and sovereignty including the territorial boundaries of the 21 Arab State created by the same Allied powers including Transjordan (Jordan).
Therefore if you accept the 21 Arab State and Jordan as assigned by the Allied Powers after WWI, you must accept Israel's sovereignty and boundaries as stated in the San Remo Treaty. The San Remo Treaty of 1920 assigned the Mandate for Palestine entirely which includes Jerusalem to the Jewish people. The terms of the San Remo Treaty of 1920 are valid in perpetuity.
If you cannot live together and you the Arabs pursue, hate terror and violence, than the only solution is a population transfer.
“Historically, there was an exchange of populations in the Middle East and Europe (over 100 million) and the number of displaced Jews exceeds the number of Arab-Palestinian refugees. Most of the million Jews were expelled as a result of an open policy of anti-Semitic incitement and even ethnic cleansing. However, unlike the Arab refugees, the Jews who fled are a forgotten case because of a combination of international cynicism and domestic Israeli suppression of the subject (recently the government of Israel has set a day for the memory of the million Jewish refugees from Arab countries). The Arab-Palestinians are the only group of refugees out of the more than one hundred million who were displaced after World War II and are intentionally remain as refugees and who have a special UN agency that, according to its mandate, cannot but perpetuate their tragedy. An open debate about the forced exodus of the million terrorized Jewish families is critical for countering the Arab/Palestinian demand for the “right of return” or right to stay and will require a more objective scrutiny of the myths about the origins of the Arab-Israeli conflict.”
President Donald Trump. Are you willing to help set-up and approve a terrorist Arab State in the United State? Your actions and deeds show you do not! Why would you want Israel to permit an Arab terrorist State in Judea and Samaria? Just see the results of giving the Arabs control of Gaza, which is now a terrorist entity that launches thousands of rockets at Israel and threatens its safety and security.
No sane leader or government would permit such a move or it will be replaced.
The same applies to many other Democratic countries, they would not put a terrorist entity in their midst.
United States is "occupied" territory - Not Jerusalem or Judea and Samaria (The whole territory of the Historical Land of Israel)
Washington, D.C., New York City, Chicago, Los Angeles, etc is far more of an "occupied" capital or territory than Jerusalem (Jerusalem and Judea and Samaria have thousands of years of Jewish history and habitation).
Europeans after creating new settlements, conquered an entire continent of North America, annihilated most of the natives, extracted its natural resources, kicked out the Mexicans and called it "America," claiming first “Philadelphia” and afterwards, the city of Washington as its capital.
Over six hundred thousand people died in the American Civil War that prevented the South from seceding and breaking apart the United States.
As regards the rest of the world, Jerusalem is the oldest capital in the world, and it belongs to the Jewish people.
The world does not recognize Jerusalem as the Jewish capital, because the world does not recognize the right of Jews to exist.
Those liberal Jews in USA and Europe and elsewhere who pander to the non-Jews by endorsing views that deny or compromise the Jewish sovereignty over The Historical Land of Israel and hoping that they would be "acceptable" are deluding themselves, they live in fantasy world, not reality. It did not help with Nazi Germany who exterminated over 6 million Jews, men, women and children; or in the past 2,500 years in the Diaspora, when the Jews were persecuted, tortured, murdered and discriminated and it will not help them today.
The Arabs/Muslims were allocated after WWI over 12 million sq. mi. with a wealth of oil reserves and the Jewish people were allocated 120,000 sq. km. of their historical territory and today they have only about 21,000 sq. km., but the Arabs/Muslims and the world nations begrudge even that small peace of our Jewish historical territory. The world nations stood idle and silent while The Arabs/Muslims terrorized, murdered and expelled over a million Jewish families with their children and confiscated all their assets, including personal valuables, businesses, homes and over 120,000 sq. km. of Jewish owned Real Estate for over 2,500 years (valued in the trillions of dollars); where was the world nations cries and demand for justice and return of Jewish Homes and Real Estate then and where are they now.
Most of the expelled Jewish families from Arab/Muslim countries were resettled in The Land of Israel, and today comprise over half the population. The European nations had better refrain from demanding that Jewish people in Israel should give up their historical land to the Arabs; since the European nations have taken over the Jewish assets, personal property (Gold, Silver, Artifacts, etc.), businesses, homes and Real Estate and many of those Jewish people and their descendants and heirs were also resettled in The Historical Land of Israel.
We the Jewish people returned to the occupied and desolate Land of Israel in the 1800’s and joined our Jewish brethren to re-blossom, revitalize and turn it into green pastures, with great economic infrastructure, industry and housing, after much toil and hard work with the help in infusion of capital and resources by our brethren in the Diaspora. We are proud and thankful to have back our historic sovereign Jewish country with an Army that can defend itself properly.
We will not surrender our land to nobody. (We should be thankful to the almighty that we are in a similar position today as we were during the time of King David). The world as whole needs Israel and The Jewish people, more than the Jewish people need the world.
Look at history every nation or society that let the Jewish people thrive and flourish, they thrived and flourished also. When a nation or society harassed, terrorized, murdered and discriminated against the Jewish people in their country, the country declined and its power and economy diminished greatly, if not disappeared altogether.
Today's time is not like the Bolshevik era when Jews were persecuted and murdered or Nazi Germany when Jews tried to escape Nazi extermination Camps, they had nowhere to go for sanctuary; even The Jewish Land of Israel aka Palestine was illegally blocked by the British.
Today the Jews have the sovereign State Israel, with its strong defense, advance technology and Medical innovations that the whole world relies on.
May we be granted and merit the honor to live and see the rebuilding of The Jewish Temple in its previous holy site on Temple Mount also known as Mount Moriah.
No Jew or Jewish government has the right to evict Jews from their historical land in Greater Israel. “Israel, including Judea and Samaria, and the land east of the Jordan River has been the land of the Jewish people since time immemorial, over 30 centuries. Judea means Land of the Jews. Never in the history of the world has there been an autonomous state in the area that was not Jewish.” There has never been a Nation known as Arab Palestine. The Arabs received over five million sq. mi. – 12 million sq. km. of territory with a wealth of oil reserves, but that was not enough. Violating international law and treaty the British allocated over three quarters of Jewish allocated land to the Arabs as the new Arab state of Jordan. Now the Arabs want more; they will not stop until they have all of Israel without the Jews. The Arab countries expelled over a million Jewish families and confiscated all their assets including businesses, homes and over 46,332 sq. mi. (about 120,000 sq. km. which is 6 times the size of Israel) of Jewish owned land for over 25 centuries. The Faisal Weizmann Agreement of January 1919 stipulated that all of Palestine is Jewish territory. No Jews are allowed to live in Jordan or in the West Bank area controlled by the Arab Palestinian Authority – Now you see it is the Arabs who are committing ethnic cleansing, just like they cleansed over a million Jewish families from Arab countries and now they are cleansing the millions of Christians and others.
The Oslo Accord is null and void as Abbas stated in the summer of 2015 at the U.N.
You; the Arabs have murdered the Jews and others and now you want to inherit them?
In view of past history of persecution; Israel and the Jews have an obsolete obligation to defend themselves at all costs. NEVER AGAIN. It must be in action not just words. No capitulation to the bias world.


For the past ~40,000 years, Homo sapiens — modern humans — has been the only Homo species on Earth. But for most of our history, there were close evolutionary cousins of ours, human but not quite like us, coexisting and evolving at the same time in different regions.
Some of our now-extinct relatives, such as the Neanderthals, are well known. Others, like the recently-discovered Denisovans or Homo naledi have hardly made it into textbooks yet. And hints of even more human forms have been found in incomplete fossils and genetic patterns, although these relatives are poorly understood. Modern humans were just one of many variations on the Homo theme.
Now, as cutting-edge techniques uncover new evidence and reassess old finds, we’re closer to knowing how many types of humans coexisted with our ancestors.
Making the Count
It’s well-established that modern humans mingled with Neanderthals and Denisovans. DNA convincingly shows the three lineages interbred in every combo: modern human/Neanderthal, modern human/Denisovan and Neanderthal/Denisovan. And if anthropologists’ interpretations are correct, we also shared the planet with Homo floresiensis, H. naledi and H. luzonensis as well as perhaps some late-surviving H. erectus. Fossils of Homo sapiens and these species overlap in time, but were geographically separated by vast distances. It’s unclear if our ancestors actually set eyes on them. Lastly, genetic patterns suggest a few more lineages in the mix (here, here), which have not yet been linked to physical fossils. For now, they’re known as ghost populations.
That brings us to seven or more types of humans since the dawn of our species, some 300,000 years ago. As a matter of convention, I refer to all Homo species as humans.
Now, some caveats.
I’m confident that number will increase in the coming years. Denisovans, H. naledi and H. luzonensis were just unveiled this decade, thanks to new excavations and — in the case of Denisovans — ancient DNA (aDNA). This relatively new technology has tremendous potential for discovering extinct lineages. In the past, anthropologists would debate if a toe bone or tooth looked similar enough to our own to be one of us. But aDNA can place fossils firmly on the evolutionary tree. For instance, the first Denisovan find was a mere pinky bone. No one would have guessed that unassuming fossil came from a previously-unknown branch of human evolution. But that’s where its DNA landed: on a lineage that diverged from modern humans over 520,000 years ago and then from Neanderthals roughly 400,000 years ago.
Next, I’m counting Homo varieties that inhabited Earth after the time when Homo sapiens actually became a species. The earliest bones widely accepted as members of our species date to 315,000 years ago from Jebel Irhoud, Morocco. The next-oldest come from the Ethiopian sites of Herto and Omo Kibish at 160,000 and 195,000 years ago, respectively. Consistent with genetic studies that estimate when all living people shared ancestors, ~300,000 is a solid back-of-the-envelope start date for our species (if, like me, you make evolutionary timelines on scraps of paper).
But human origins began long before modern humans. The ancestors of chimpanzees and humans parted ways over 6 million years ago. Since then, the branch that modern humans are on has included many species called hominins. Some continued evolving to become present-day people; most went extinct.
Early hominins, which resembled upright walking apes, included Sahelanthropus, Ardipithecus and Australopiths like the Lucy fossil. By 2.8 million years ago certain hominins had sufficiently large brains and modern-looking anatomies for anthropologists (somewhat arbitrarily) to classify them as members of our genus Homo — or as we call them, humans. For millions of years, Earth sustained numerous coexisting types of hominin, and then human. So the question, “how many contemporaries did we have?” depends on the timeframe.
Since Homo sapiens emerged, seven or more human types inhabited the planet. Today, we’re the only ones left. It’s an odd time in human evolution.


What is ADHD?
from The Diary of a First Grade Teacher
What is ADHD? It's a term you’ve probably heard before ... In the past, it was used freely and applied to anyone who had trouble focusing on ANY one thing at a time.
But that’s not a fair and reliable method to determine if someone really has ADHD. To know for sure requires a clinical diagnosis.
ADHD stands for "attention deficit-hyperactivity disorder.” Some people use it interchangeably with the term, ADD, but they shouldn’t confuse the two.
ADD stands for “attention deficit disorder” and refers to people who have attention deficit, but there’s no hyperactivity involved with it.
Learning more about what ADHD is and isn’t can help you determine if your child needs testing.
What is ADHD?
In the Classroom ...
Teachers are often asked, "What is ADHD?" Parents want to know not only what it is, but specifically how can it affect a child in the classroom.
A child with undiagnosed ADHD will likely have difficulty of some kind or other. And while teachers can and will tell you about your child’s school behavior, we do not make clinical diagnoses ...
But when a teacher sees a student constantly struggling - having problems concentrating and paying attention - we report it to you.
As teachers and parents we know that over the course of any typical day any child may experience restlessness and inattentiveness, especially if the child is tired, sleepy, or sick.
So, how can you tell the difference between the two?
To see what sets people with ADHD apart, health professionals look at the area of the brain responsible for clarity, mental focus, and activity. What they’ve discovered may be surprising to you …
The brains of people with ADHD are wired differently.
This means that even when the child tries to “settle down,” his mind just doesn’t want to comply. You can tell him to relax, focus, and pay attention all day long, but he’s incapable of making his mind and body cooperate.
So the question is - as a parent or guardian - how do you know if your child is suffering from a normal bout of fidgeting or really has ADHD?
Signs and Symptoms of ADHD
There are three main categories of ADHD: hyperactivity, inattention and impulsivity. Each has similar symptoms, but they can be distinguished enough to determine if your child has one, two, or all three of the components.
Signs of Hyperactivity
Signs of Impulsivity
If your child has exhibited any of these signs day in and day out – at school and at home - the next step is to seek more information.
You can ask the counselor or the social worker at your child’s school if they can help you. Chances are good they can OR they will have resources available to refer you to someone for testing.
A professional assessment can give you more information into the condition and answer any questions you may have. No one wants to see a child hurting in any way, including struggling to learn.


Why does the Torah need to add "Kein Tarimu Gam Atem"?
Rashi: To teach the Levi'im that they are required to separate Terumah from their Ma'aser just as Yisrael separate Terumah from their crops - because Ma'aser is their (the Levi'im's) inheritance.
Moshav Zekenim (from Gitin 23b): Just like you are a Yisrael, also your Shali'ach must be a Yisrael.
Why does the Torah say "le'Aharon ha'Kohen" (who never entered Eretz Yisrael)?
Torah Temimah #1 (citing Sanhedrin, 90b): This teaches us that, one day, Aharon will come back to life and we will give him Terumah - in Eretz Yisrael! 1
Torah Temimah #2 (citing Sanhedrin, 90b): This teaches us that one should give one's Matnos Kehunah to a Kohen Talmid-Chacham (like Aharon ha'Kohen), and not to an Am ha'Aretz.
A hint at Techiyas ha'Meisim.