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Genetic / taxonomic issues for the Cat Specialist Group
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Different definitions of the term 'subspecies' exist, but the one that I will use here, derived from Study.com, is "a population of a species that is genetically and geographically different to another population of the same species."
In 2017, the Cat Classification Taskforce of the Cat Specialist Group, which can be said to include a "who's who" of experts on of cats, such as Shu-Jin Luo and Urs Breitenmoser, published a revision of subspecies of felids: https://repository.si.edu/bitstream/hand...sAllowed=y There are 2 main issues with the revision of 2017 that I can see: 1) The CSG admitted uncertainties regarding particular subspecies, such as for the bobcat and cheetah 2) Certain revisions, such a for the tiger and leopard, are controversial because they are not supported by all genetic assessments.
Lion (Panthera leo)
Initially, several subspecies of African lions were described, including the Barbary lion (Panthera leo leo) of the Maghreb (Northwest Africa), the Senegal lion (Panthera leo senegalensis) of West Africa, and the Cape (Panthera leo melanochaita) and Kruger lions (Panthera leo krugeri) of South Africa, with the Asiatic lion (formerly Panthera leo persica) considered to be a separate subspecies. At some point, it was considered that all African lions belong to the same subspecies, Panthera leo leo, with the Asiatic lion being a separate subspecies. Eventually, genetic tests, like those of Barnett et al. and Antunes et al. in the 2000's, showed that genetically, certain African lions, such as the Barbary lion, were more closely related to the Asiatic lion than to other African lions, such as the Kruger lion, thus making the traditional recognition of the African and Asian lions as separate subspecies questionable. In 2017, the CSG recognised lions in Asia and Northern, Western and Central Africa as belonging to the subspecies Panthera leo leo, and those in Eastern and Southern Africa as belonging to the subspecies Panthera leo melanochaita, but there is a problem, the 2 subspecies appear to overlap in the Northeast African country of Ethiopia, judging by the work of Bertola et al., which would mean that Ethiopian lions (formerly Panthera leo roosevelti or Felis leo roosevelti, in honor of the US President Theodore Roosevelt (https://archive.org/stream/smithsonianmi...3/mode/2up), but also treated as belonging to the Masai subspecies by Haas et al. and Wozencraft) are neither purely Panthera leo leo nor Panthera leo melanochaita, but a mixture (Panthera leo leo × Panthera leo melanochaita or Panthera leo leo + Panthera leo melanochaita), and the Cat Specialist Group put a question mark over the Horn of Africa in Page 72: As mentioned here, it's not necessarily the case that geneticists like Bertola found mixed up lions (Panthera leo leo × Panthera leo melanochaita), it's to do with where they found Northern (P. l. leo) and Southern lions (P. l. melanochaita) in Ethiopia or Northeast Africa, which suggests that their ranges overlap there:  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author An Ethiopian lion (formerly Panthera leo abyssinica or Panthera leo roosevelti) discovered in Bale Mountains National Park, Northeast Africa, image by The National Geographic:  *This image is copyright of its original author Additionally, not all Central African lions, particularly Northeast Congolese lions (formerly P. l. azandica) are of the Northern subspecies (P. l. leo), as indicated above. A number of them are of the Northern subspecies, but others are of the Southern subspecies (P. l. melanochaita). Northeast Congolese lion (formerly Panthera leo azandica) at Virunga National Park, Central Africa, photo by Adrian Treves:  *This image is copyright of its original author
Tiger (Panthera tigris)
People would be familiar with the following 9 subspecies or types: 1) The Bengal tiger (Panthera tigris tigris) in South Asia 2) The Caspian tiger (Panthera tigris virgata) in Afghanistan (South Asia), and Central and Southwestern Asia, and possibly Eastern Europe, which is genetically similar to: 3) The Amur tiger (Panthera tigris altaica) in Northeast Asia 4) The Javan tiger (Panthera tigris sondaica) in the Sunda Islands 5) The South Chinese tiger (Panthera tigris amoyensis) in East Asia 6) The Balinese tiger (Panthera tigris balica) in the Sunda Islands 7) The Sumatran tiger (Panthera tigris sumatræ) in the Sunda Islands 8) The (Northern) Indochinese tiger (Panthera tigris corbetti) in Southeast Asia 9) The Malayan or Southern Indochinese tiger (Panthera tigris jacksoni synonym Panthera tigris malayensis) in Southeast Asia The originally described 8 subspecies by Nowell and Jackson, pages 148–149: A Malayan tiger, credit: Tigers-World  *This image is copyright of its original author A map of the distribution of tigers by Vratislav Mazák in 1981: Now here is the history between the taxonomic disputes regarding the tiger that I know of: In 2006, Mazák and Groves published a study on the Sumatran, Javan, Balinese and Indochinese tigers of Southeast Asia. They said "The taxonomic affinity of Southeast Asian tigers is re-investigated. Specimens of four traditionally recognized subspecies are examined using various craniological methods, including multivariate craniometric and phenetic analysis. Sumatran tigers differ absolutely (100%) from the geographically neighbouring mainland form P.t.corbetti; the Javanese tiger is also 100% distinguishable from the Sumatran. They are therefore regarded as two distinct species (P.sumatrae, P.sondaica) under the Phylogenetic Species Concept (PSC). The Bali tiger is classified as a subspecies of the Javanese tiger, Panthera sondaica balica." In 2015, Wilting et al. published a study on many sets of data on traits of tigers (morphological (craniodental and pelage), ecological, molecular) that were used to differentiate them into subspecies. They claimed "Our results support recognition of only two subspecies: the Sunda tiger, Panthera tigris sondaica, and the continental tiger, Panthera tigris tigris, which consists of two (northern and southern) management units," with the northern 'unit' of the mainland Asian subspecies being composed of the Amur and Caspian tigers (hence the name "Northern tigers" for them, collectively), and the southern 'unit' being the Bengal, Northern Indochinese, Malayan and South Chinese tigers. Kai Kupferschmidt then published an article in the same year, under the heading "Controversial study claims there are only two types of tiger", in which he mentioned differences in opinion about the study of Wilting et al. For instance, Urs Breitenmoser, a zoologist at the University of Bern, who was not involved in the study, and is a co-chair of the Cat Specialist Group of the International Union for Conservation of Nature (the organization that draws up the red list of threatened species) said that the paper would "surely cause a stir," but that he found "the work quite convincing and in keeping with other findings in recent years,” like a paper that suggested the Caspian and Siberian tigers were the same subspecies, and that the Cat Specialist Group would look at this proposal as well. However, Shu-Jin Luo, a geneticist at Peking University in Beijing who works on endangered species (and whom I will refer to later), was skeptical of the study, arguing that the 9 traditionally recognized subspecies could be distinguished genetically, and that that should be enough, saying "Genetic data is much more reliable and objective than morphology." In 2017, the Cat Classification Taskforce of the Cat Specialist Group, in line with the work of Wilting et al., and what Breitenmoser said, decided to recognize only 2 subspecies of tigers (like with the lion): the Continental or Mainland Asian tiger (Panthera tigris tigris; comprising the Bengal, North Indochinese, Malayan, South Chinese, Amur and Caspian tigers), and the Sunda Island tiger (Panthera tigris sondaica; comprising the Javan, Sumatran and Balinese tigers), while recognizing that the Malayan tiger had a unique mtDNA haplotype, likely because it is close to the ancestral lineage. The border between the ranges of the Continental and Sunda tigers is the Strait of Malacca between the Malayan Peninsula (where the Malayan tiger is present) and the Sunda Island of Sumatra. The Strait of Malacca between the Malayan Peninsula and Sumatra by Shizhao:  *This image is copyright of its original author However, in 2018, CSG members Driscoll and Luo rebelled against the classification of tigers into only 2 subspecies, by contributing to a study which used the whole-genome sequencing approach for analysis, which was based on 32 tiger specimens. From this, they argued that tigers were divided into 6 monophyletic clades, and hence 6 living subspecies: the Bengal (P. t. tigris), North Indochinese (P. t. corbetti), Malayan (P. t. jacksoni), South Chinese (P. t. amoyensis), Amur (P. t. altaica) and Sumatran tigers (P. t. sumatræ).
Leopard (Panthera pardus)
The CSGhad grouped the Zanzibari (formerly Panthera pardus adersi, possibly extant) and mainland African leopards (including the Barbary leopard (formerly Panthera pardus panthera) of the Maghreb (Northwest Africa)) into one subspecies (Panthera pardus pardus), and said that the Sinai (Panthera pardus jarvisi) and Arabian leopards (Panthera pardus nimr) could be the same subspecies as African leopards, and all other leopards in Asia and European Russia (which has Caucasian leopards (Panthera pardus ciscaucasia / tulliana)), including the Sri Lankan leopard (Panthera parsus kotiya), could be one subspecies (Panthera pardus fusca), with the exception of the Javan leopard (Panthera pardus melas): "Luo et al. (2014) published a further molecular study which included more samples from Indochina and the Malay Peninsula. The phylogeographical patterns are not clear for all putative subspecies. For example, P. p. kotiya is close to East Asian leopards based on mtDNA, but groups with P. p. fusca based on microsatellites (Uphyrkina et al. 2001). P. p. saxicolor also seems to group differently depending on the analysis used (Uphyrkina et al. 2001, Luo et al. 2014). Luo et al. 2014 show that P. p. fusca is diphyletic based on mtDNA, which was not found in previous studies. Khorozyan et al. (2006) analysed the skull morphometrics of southwest Asian leopards, and concluded that saxicolor and ciscaucasica were consubspecific, but retained tulliana and millardi as distinct. However, sample sizes were very small for some of these putative subspecies. Rozhnov et al. (2011) examined sequences of mtDNA (NADH5) and 11 microsatellites from southwest Asian leopards. They concluded that all were consubspecific from Afghanistan through Iran to the Caucasus, but no western Turkish specimens (tulliana) were analysed. Here japonensis is included in orientalis; there is no clear biogeographical barrier between these two forms which appear to form a cline in northeastern Asia. As the molecular differences between continental Asian leopards are very small compared to differences in Javan leopards (P. p. melas; Wilting et al. 2016), there could be a case for including all Asian subspecies, excluding melas, in a single Asian subspecies. These conflicting results from different studies suggest that more comprehensive sampling is required from throughout the range, taking advantage of museum specimens of known provenance. Until such a study is carried out, we propose the following conservative arrangement of subspecies: Panthera pardus pardus (Linnaeus, 1758). Distribution: Africa. Comment: Although there are two principal mtDNA clades in Africa, they both occur in southern Africa and appear to be partly sympatric. Thus it would appear that no subspecies can be distinguished within Africa. However, more comprehensive sampling is needed. Panthera pardus tulliana (Valenciennes, 1856; 1039), including ciscaucasica, saxicolor. Type locality: Ninfi, village situé à huit lieues est de Smyrne [near Izmir, Turkey]. Holotype: MNHN-ZM-MO-1849-20 mounted skin (skull inside). Distribution: Turkey, Caucasus, Turkmenistan, Uzbekistan, Iran, Iraq, Afghanistan and Pakistan. Comment: This is the earliest name for leopards from South West Asia, and hence includes saxicolor and ciscaucasica. If tulliana proves to be distinct from other southwest Asian leopards, ciscaucasica is the earliest available name. Panthera pardus fusca (Meyer, 1794). Distribution: Indian subcontinent, Burma and China. Panthera pardus kotiya (Deraniyagala, 1949). Distribution: Sri Lanka. Panthera pardus delacouri (Pocock, 1930b). Distribution: SE Asia and probably southern China Panthera pardus orientalis (Schlegel, 1857), including japonensis. Distribution: Eastern Asia from Russian Far East to China. Panthera pardus melas (Cuvier, 1809; 152). Distribution: Java. Comment: Distinct ancient island form (Meijaard 2004, Gippoliti & Meijaard 2007, Uphyrkina et al. 2001, Wilting et al. 2016). Panthera pardus nimr (Hemprich and Ehrenberg, 1832). Distribution: Arabian Peninsula. Comment: Distinctively small form, but may prove to be consubspecific with subspecies pardus, although should be retained as a separate management unit if so." As for Central Chinese leopards, like at Wolong Reserve in Sichuan, where they may attack sub-adult pandas, their exact taxonomic status is unclear, being alternatively grouped under the P. p. japonensis, P. p. delacouri, or even P. p. fusca. In 1993, Brakefield noted that just as there is a North Chinese leopard, there is also a South Chinese leopard, which was "much more golden yellow" in colour, had shorter fur, and which people thought might be of the Indian (Panthera pardus fusca) or Indochinese (Panthera pardus delacouri) subspecies, or a subspecies of its own (possibly Panthera pardus sinensis), and Uphyrikina et al. said "Teeth of ancient leopards found in southern China and dated from the Middle of Pleistocene were similar to the recent subspecies P. p. sinensis; this led to the hypothesis of local evolution in eastern and southeastern Asia (Hemmer 1976)." Stuffed leopard for testing pandas at Wolong Nature Reserve, Central China, credit: Alamy  *This image is copyright of its original author Back to African leopards, though the CSG grouped them into 1 subspecies, they admitted that 2 principal mtDNA clades in Africa, particularly in southern Africa, and thus that they appeared to be partly sympatric, so though they couldn't distinguish between African leopards as different subspecies, "more comprehensive sampling" was needed. That's not the only issue facing African leopards. In another thread, @chui_ posted excerpts from the study by Anco et al. (2017): "Historical mitochondrial diversity in African leopards (Panthera pardus) revealed by archival museum specimens Abstract Once found throughout Africa and Eurasia, the leopard (Panthera pardus) was recently uplisted from Near Threatened to Vulnerable by the International Union for the Conservation of Nature (IUCN). Historically, more than 50% of the leopard's global range occurred in continental Africa, yet sampling from this part of the species' distribution is only sparsely represented in prior studies examining patterns of genetic variation at the continental or global level. Broad sampling to determine baseline patterns of genetic variation throughout the leopard's historical distribution is important, as these measures are currently used by the IUCN to direct conservation priorities and management plans. By including data from 182 historical museum specimens, faecal samples from ongoing field surveys, and published sequences representing sub-Saharan Africa, we identify previously unrecognized genetic diversity in African leopards. Our mtDNA data indicates high levels of divergence among regional populations and strongly differentiated lineages in West Africa on par with recent studies of other large vertebrates. We provide a reference benchmark of genetic diversity in African leopards against which future monitoring can be compared. These findings emphasize the utility of historical museum collections in understanding the processes that shape present biodiversity. Additionally, we suggest future research to clarify African leopard taxonomy and to differentiate between delineated units requiring monitoring or conservation action. ... Leopards exhibited population structuring at large geographic scales (West, Central-East/Central-Southern, and Southern Africa), suggesting strong evidence against panmixia in this species. AMOVA and pairwise FST analyses support differentiation in the ND-5 locus spanning five major haplogroups: West Africa, Coastal West-Central Africa, Central- East-Africa, Central-Southern Africa, and Southern Africa. Distinction between CEA and CSA as two independent regional populations is supported by pairwise FST analyses (Figure 4). Although still high, FST[CEA-CSA]¼0.40, was the lowest among all African leopard population comparisons. CSA showed higher levels of differentiation from WA and CWCA leopard populations, than the latter two did to CEA, indicating that CSA leopards are reproducing in isolation from neighbouring populations (Figure 4). Furthermore, CSA exhibited the highest levels of differentiation when compared with the two selected Asiatic subspecies: FST[CSA-nimr]¼0.98 and FST[CSA-saxicolor]¼0.97 (Figure 4). The African leopard harbours a greater degree of genetic diversity than previously indicated and is partitioned in a pattern providing strong support for significant genetic subdivision. Our pairwise FST analyses using mtDNA revealed leopard populations throughout sub-Saharan Africa retain highly divergent copies of the ND-5 locus on levels approaching, and in some instances exceeding, FST values observed between Asiatic populations (Arabian and Persian leopards) presently recognized by the IUCN as separate subspecies (Figure 4). AMOVA revealed population structuring indicating a lack of gene flow between larger geographic regions (West Africa, Central-East/Central-Southern Africa, and Southern Africa) and among all the populations within regions. Two populations, CEA and CSA showed decreased pairwise differences relative to other populations, which could be an artifact of decreased sampling. Lastly, the star-like phylogeny, widespread distribution, and connectedness of the H10 haplotype points to a likely origin of diversity for the ancestral haplotype of this locus in Central and East Africa. We caution this work may not fully express the degree of genetic diversity present in African leopards, especially given sampling deficiencies in North Africa, parts of West Africa, and in Northeastern Africa. This study has raised important questions regarding the taxonomic status of leopards in Africa. First, these findings support a distinction between African populations and Arabian and Persian leopard populations. We found additional strong support for an East-West split in African leopards, which may correspond to previously hypothesized taxonomic groupings (Figure 1, Table 1) and is congruent with numerous recent phylogeographic analyses of widespread African taxa (Moodley & Bruford 2007; Lorenzen et al. 2012; Dobigny et al. 2013; Smitz et al. 2013; Bertola et al. 2016; Fennessy et al. 2016). More sampling is needed to accurately delineate geographic features acting as potential barriers to gene flow (e.g. Sanaga River in Central Cameroon), while a suture zone has been identified between CWCA and CEA populations (Figures 2 and 3). In addition, we have identified previously unrecognized levels of genetic diversity in historical collections of African leopards not represented in contemporary leopard populations. While only based on mtDNA, the reconstruction of a haplotype network using novel samples of African leopards has reopened a >15-year-old conversation regarding African leopard diversity and taxonomy. We acknowledge that our results are limited by the use of mtDNA, and consequently single locus data. We therefore, strongly recommend multilocus sampling to investigate whether African leopards exhibit evidence of discordance between mitochondrial and nuclear markers (Toews & Brelsford 2012). These findings will provide the foundation for our ongoing analysis of temporal changes in phylogeographic patterns using sequence capture from historical collections, which will contribute to management and planning strategies to conserve remaining genetic diversity in the African leopard." Image of the Atlas lion, brown bear and leopard from the Maghreb (Northwest Africa), by Joseph J. Ortega:  *This image is copyright of its original author Video:
@peter @Shadow @Rishi @GuateGojira @Sully In "Man-Animal Interactions ...", @Spalea had quoted this article as saying that a new genetic study on lions had been published this year, so I checked the original article, which was linked to in the former, and it says something interesting about the issue of subspecies: https://www.pnas.org/content/early/2020/...1919423117
"Implications for Conservation. Historically, up to 11 subspecies of modern lions have been recognized (41). In 2017, the number was reduced to two in light of the results of molecular studies (42): 1) P. leo; in Asia, West Africa, and Central Africa and 2) P. leo melanochaita; in East and South Africa. Here, we show that although Central African lions cluster with P. leo leo in mtDNA-based phylogenies (SI Appendix, Fig. S1), their genome-wide ancestry shows higher affinity with P. leo melanochaita (Fig. 1B and SI Appendix, Fig. S19). Therefore, our results suggest that the taxonomic position of Central African lions may require revision. We caution, however, that our data are based on genome-wide data from a single wild-born Central African lion (SI Appendix, Table S1), and a recent study using whole-genome and microsatellite data suggests that Central African lions from the Democratic Republic of Congo (DRC) and Cameroon preferentially cluster with P. leo leo (26). In addition, gene flow in Central and West Africa may have been common in the past (Fig. 3B): both lineages probably lived in sympatry for long periods of time and their genetic divergence is not high. In any case, further studies should increase sampling from West and Central Africa to fully resolve this issue." This study has multiple authors, including Ross Barnett, Stephen O’Brien, and Nobuyuki Yamaguchi. The latter 2 are members of the Cat Specialist Group who had worked on lions before, and had cooperated with fellow CSG members Shu-Jin Luo and Carlos Driscoll, among others, to publish the study in 2009, which showed that the Amur and Caspian tigers were genetically close enough to be considered the same subspecies. O’Brien, Luo and Driscoll had also contributed to the study, published in 2018, about there being 6 monophyletic clades of tigers, or 6 living subspecies of tigers, after the main CSG had published a taxonomic revision of felids in 2017, in which they argued that there were only 2 subspecies of lions and tigers, as mentioned above in this thread. Around the same time, Barnett and Yamaguchi had contributed to a study, published in 2018, in which they mentioned that there were phylogenetic differences between populations that were considered to be within the same subspecies (using the CSG's classification), such as Western and Central African lions, without necessarily arguing against the classification of 2 subspecies for lions. To put it simply: * In 2009, Barnett and CSG members O’Brien, Yamaguchi, Luo and Driscoll said that the Caspian and Siberian tigers were genetically close enough to be considered as belonging to the same subspecies * In 2017, the CSG published their controversial classification, in which they recognised only 2 subspecies of lions and tigers, respectively the Northern lion (Panthera leo leo), Southern lion (Panthera leo melanochaita), Continental or Mainland Asian tiger (Panthera tigris tigris) and Sunda Islands' tiger (Panthera tigris sondaica) * Then CSG members O’Brien, Luo and Driscoll 'rebelled' by contributing to a study, published in 2018, to say that there were 6 living subspecies of tigers, while Barnett and CSG member Yamaguchi contributed to a study, published in the same year, in which they mentioned that there were phylogenetic differences between populations of lions within the same 'subspecies' * Now in 2020, Barnett and CSG members O’Brien and Yamaguchi have contributed to a study, in which they and others suggest that the taxonomic position of Central African lions may need to be revised! 
Really interesting stuff there, just as Zambia (if I remember correctly) is the corridor between eastern and southern melanochaita, central Africa seemed to serve as that for leo and melanochaita.
Among us on the forum, which version of both lion and tiger subspecies classification do you subscribe to? I appreciate none of us are geneticists (that I know at least) but I'm interested to hear general opinions anyway. (05-09-2020, 10:08 AM)Sully Wrote: Really interesting stuff there, just as Zambia (if I remember correctly) is the corridor between eastern and southern melanochaita, central Africa seemed to serve as that for leo and melanochaita. Ultimately, it can depend on how you define a 'subspecies'; if you're ready to accept the idea that Bengal tiger is the same subspecies as say Indochinese and Siberian tigers, because Continental or Mainland Asian tigers are more closely related to each other than they are to the Sumatran, Javan, and Balinese tigers (and possibly Bornean tigers, see this thread) in the Sunda Islands, then you could accept the idea that the Asiatic or Eurasian lion is the same subspecies as say Barbary and West African lions in northern parts of Africa, because they are more closely related to each other than they are to lions in southern parts of Africa (like Tanzania, South Africa and Namibia), and that's what the Cat Classification Taskforce of the Cat Specialist Group did in 2017. Otherwise, if you would question the idea that the Asiatic or Eurasian lion is the same subspecies as lions in northern parts of Africa, since they are geographically distinct at least, then you could find the idea that there are only 2 subspecies of tigers controversial, on both genetic and geographical grounds (for instance, Bengal tigers are both genetically and geographically distinct from Amur tigers), and it certainly was for some CSG members (Stephen O’Brien, Shu-Jin Luo and Carlos Driscoll): https://www.sciencemag.org/news/2015/06/...ypes-tiger, https://www.cell.com/current-biology/ful...18)31214-4?
An opinion:
This study proposes good reflections (even for a short time, due to the few specimens used - only 1 in Central Africa). The fact that Dr. Ross Barnett is present, is very significant and shows that his study published in 2014 was complemented with more subsidies. The improvement of evaluation methods, in the whole genome instead of mtDNA, has brought new horizons and, to them, we must understand these new implications. Conceptually, the "ancestry" understood here shows that all lions, whether Barbary, Western or Indian, all have a genome of lions from Southern / East Africa. The most recent flows identify their paths to conservation - see genetic improvements - be in the establishment of a new population in North Africa, or in the mixing of genes with Indian lions. An important issue of the Article is in the final lines - in the wolves of the Royalle Island - where mixing genes did not produce specimens more able to survive, making it implied that deeper genetic knowledge is needed when establishing gene mixing - linking the functioning of genes to multiple contexts , both physiological and ecological. Issues closely linked to geneticists and lion ecologists. With a conservationist bias, I prefer to reduce subspecies, so, answering your question @Sully, I prefer the division of tigers into two subspecies: continental and insular. In lions, the understanding, before this scientific article, Dr. Laura Bertola (2015) recognized, via mtDNA, three clades in Africa: North, West and Central; eastern and southern, observing microsatellite Loci criteria and a very small number of different genes in each of these three groups (it seems to me that a wider range of unique genes would be needed to distinguish species from subspecies, define a percentage of different genetic factors would be a good point). Conservation implications basically lie in the same path as this article. The IUCN has not changed its diagnosis in any way, even recognizing these new criteria, so we continue to have two subspecies of lions. Until now, a right strategy. I don't understand why so many people prefer the existence of countless subspecies. In the recent past, lions were distributed according to unscientific criteria - lions from a single country were classified as subspecies: size or color of mane, size of tuft of hair on the tail ... anecdotal criteria. "Genetic diversity is the result of combining the time factor with geographic isolation." Many cling to very recent time factors. In this field, lions from the Atlas are closely linked to Western lions due to the coastal paths. Its close proximity to the central lions is not only linked to the connection between western and central clades, but also at the time of the "Green Sahara", a true bridge between lions from the north and the center of Africa, not forgetting the coastal paths through Egypt and Libya (what I believe is that this last corridor must have closed around 3,000 or 4,000 years ago - as a result of large-scale human occupation). In Roman times, the final connection was to Western lions, despite the Sahara desert having a milder climate and temperature than it is today and relic lion populations must have remained in parts of the A-haggar, Tassili, Air Moutains mountains. At the Ennedi plateau, lions were only extirpated in the 1920s. From north to center Africa was connected. These recent studies demonstrate that the Rift Valley did not divide the lion populations, as it did with a series of antelopes (the most morphologically healthy case is the eland Lord Derby). So Asian lions are the most genetically distant lion population - the article suggests up to 30,000 years of separation, which does not indicate flow restriction, the path has remained clear for many millennia. It is plausible to maintain two subspecies due to inherently geographical distance factors. The double infraorbital form of Asian lions (which is not a characteristic of the subspecies, since it is not present in all individuals) is due to monogamous factors. A genetic defect. The fold does not justify a differentiation, nor is it present in 100% of Indian lions, and 3% of African lions also have this fold. I prefer to join efforts and not share efforts. I see much more benefits from developing lion reintroduction / translocation projects when we can use multiple individuals, from many origins and locations. Although geographic proximity is very important, as it better enables individuals to be located in terms of pathogens and other diseases endemic to the area. In the case of Indian lions, there is no way to infer this type of prevention. Subspecies make it more attractive for the emergence of local conservation projects, from a simplistic point of view this is not bad. After all, all wild animals must be saved, each country must maintain nature reserves whether they represent their nature in the best way. However, it keeps more people in the conservation business, more NGOs, more fundraising campaigns, greater fragmentation of the financial flow to places that, ultimately, will not be successful in conserving the chosen object. The question also remains: it is ethical to divide a species to facilitate people, even well-intentioned, to obtain financial flow from people who believed in the existence of genetically unique lions. Geopolitics of lions, tigers and every animal that generates greater sentimental attachment. Conservation is big business, and protecting cats is the culmination of the collection. There is great political and economic interest behind the taxonomic changes. (05-24-2020, 08:41 AM)Matias Wrote: An opinion: @peter @Shadow @Rishi @GuateGojira I don't necessarily reject the idea that the number of subspecies had to be revised, because they were initially based on both morphological and geographical grounds, such as the Barbary and West African lions, and the Amur and Bengal tigers, but an issue to bear in mind here is practical implications. Even if say the Amur tiger is a member of the same subspecies as the Bengal tiger, that is the "Continental / Mainland Asian tiger (Panthera tigris tigris)", for the sake of argument, that doesn't mean that you can transfer Bengal tigers from India or South Asia to the Amur region, where the relatively endangered Amur tiger lives, to boost the population of "Mainland tigers" there, does it? The Bengal tigers (which are used to hot or humid jungles or forests, aside from those in the Himalayan region) would have to adjust to the freezing climate of the Amur region, but they don't even have the thick winter fur which their Siberian relatives have, so even if they are within the same subspecies, they are still different populations of tigers which are used to different climates, not to mention that significant genetic differences do exist between them. Bengal tiger in the hot forest of Ranthambhore National Park, India: https://mapandmagnets.com/planning-tiger...ore-india/  *This image is copyright of its original author Amur tiger in the temperate region of the Sikhote-Alin Mountains, Russia: https://www.globalgiving.org/projects/sa...hote-alin/  *This image is copyright of its original author
@BorneanTiger
I'll clarify or, who knows, complicate things further. Conservation practices actions for a certain feline are not related to the establishment of subspecies. Amur tigers are adapted to a unique environment and their conservation value is recognized internationally; and efforts will continue to your aid regardless of a change in your taxonomic conceptualization. In other words, it is not necessary to recognize any living being that occupies a unique ecological area, within its natural range of existence, to have immeasurable conservation value. We can use the same criteria for the tiger that inhabits the "Sunderbans". No specialist in big cats will make any proposal to mix Indian tigers with wild tigers from the Russian Far East. See "adapted desert lions" and their unique conservation value. All shared efforts to safeguard them in northwestern Namibia are independent of conceptualizing them as a subspecies. Dividing a species, depending on many factors, can facilitate local conservation action, as well as deter this action. When a subspecies has extremely small numbers, saving them requires much more than a good project and a good amount of money. See tigers recently extirpated out in Vietnam, Laos and Cambodia. What is the possibility of Thailand (with small numbers of tigers) providing a good number of individuals for future reintroduction projects? Any species of feline must have separate conservation units, the entire range of occupation is important and largely represents its genetic variation, as much as it works in establishing metapopulations. I believe, based on what I read, that there are no profound genetic differences between Indian and Amur tigers. There are studies that do not follow this reasoning. Geneticists have not yet established objective and consensual criteria, and another 30 arguments, grouped or not, are said in the statements to subdivide a species. Despite records in museums for specimens such as tigers in southern China, java, bali are scarce, the same specimens have been shared by genetic research studies that have reached different results, despite analyzing the same sources. By division criteria, until a few decades ago, China would have in its territory four subspecies of tigers. In Southeast Asia, in terms of phylogeography, what natural agents could have separated tiger populations by enough to justify establishing so many subspecies in this region? The important thing would be to know what percentage of genetic variation these continental tigers have. Still, biologists recognize that this is a terrible way to understand the evolutionary processes that give rise to differences between populations. One of the central points of the discussion was that morphology, behavior or different DNA markers may have different patterns of geographic variation. Each of them constitutes a part of the complex evolutionary history of a species and, in some cases, its adaptations to the different environments that it occupies today or occupied in a more remote temporal past. |
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