Population genetics and spatial structure in two andean cats (the Pampas cat,Leopardus pajeros and the Andean mountain cat, L. jacobita) by means of nuclear and mitochondrial markers and some notes on skull biometrics

In this chapter, we show complementary results to the works of Cossíos et al., (2009,2012), on the genetic structure and phylogenetics of two small Andean cats, the Pampascat (Leopardus pajeros) and the Andean mountain cat (Leopardus jacobita). In thepresent study we increased the samples sizes to 235 individuals for L. pajeros and 115individuals for L. jacobita, effectively making these samples the largest to date for thesetwo species. We analyzed five microsatellites for L. pajeros and seven microsatellites for L. jacobita as well as the hypervariable domain 1 (HVS-1) of the mtDNA control regionfor both species. The main results obtained were as follows: 1- The levels of genediversity for L. pajeros with microsatellites were considerable higher than in L. jacobita(average H = 0.73 vs. 0.42, respectively), with the first similar to other Neotropical felidsbut the second one lower than other Neotropical felids and many other Neotropicalmammals analyzed from this point of view. The same was recorded for mtDNAsequences, with the Pampas cat ( Π= 0.0513) presenting more than 10 times highernucleotide diversity than the Andean mountain cat ( = 0.0047). The sample which couldrepresent the putative morphological subspecies, L. p. budini, was that which yielded thehighest levels of gene diversity. This could mean that this is the original L. pajeros formfrom which the other forms derived. Alternatively, the northern area of Argentina, whereL. p. budini occurs, could be a hybridization zone among several L. pajeros forms. 2-Microsatellite heterogeneity for the Pampas cat was significant but it was relatively lowwith regard to the high genetic heterogeneity found for L. jacobita for microsatellites. FormtDNA, the genetic heterogeneity was very high and similar for both species. This couldindicate that for the Pampas cat the gene flow is male biased, meanwhile the Andeanmountain cat populations are hardly isolated in the high land deserts of the Andes and thegene flow is more restricted for both males and females. Also this analysis puts in doubtthat L. pajeros pajeros and L. pajeros crucinus are two different subspecies. Furthermore,this analysis revealed that if the different gene pools determined in L. pajeros areclassified as different subspecies, then four different subspecies, or at least, four differentevolutionary lineages must be consider in L. jacobita. 3- The assignation analysespresented relatively low percentages of correct assignation for L. pajeros, while thepercentages of adequate assignation for L. jacobita were very high. This is related withthe fact that gene flow estimates among the populations of the Pampas cat areconsiderably higher than for the populations of the Andean mountain cat for nuclearmarkers. 4- L. pajeros presented more evidence of population expansions during itshistory for microsatellites than did L. jacobita. For mtDNA, both species did not revealtraces of population expansions and L. jacobita showed a trend indicative of a moderatebottleneck. 5- Both species showed 4-5 % of mutations with multiple steps and differentmutation rates for the microsatellites employed. 6- The effective number estimates werearound 10 times higher for L. pajeros than for L. jacobita independently of theprocedures employed. The effective sizes for L. pajeros ranged from 80,000 to 330,000and for L. jacobita ranged from 12,000 to 38,000. However, these estimates seem to behigher than the current census sizes. The procedures of Hill (1981) and Pudovkin et al.,(1996) were not useful for effective number estimations in this case. 7- Both speciespresented significant spatial structure related with isolation by distance and monotonicclinal trends, but this spatial structure was more developed in L. jacobita. Around 35 %of the genetic differences were explained by the geographical distances among thepopulations in L. pajeros, while around 64 % of the genetic differences were explainedby geographical distances in L. jacobita. 8- The northern Chilean Pampas cat populationseems to be an extension of the Peruvian and north Bolivian L. p. garleppi incontradiction with García-Perea (1994), who denominated that population as a newsubspecies L. colocolo wolffsohni. Nevertheless, more samples of that region are neededto have total clarity of what Pampas cat is living there. Additionally, in Bolivia, wedetermined the existence, at least, of two putative subspecies (garleppi and steinbachi).Finally, although molecular conclusive studies are needed, the first molecular studiesindicate that the existence of a unique Pampas cat species is more probably than threedifferent species such as García-Perea (1994) proposed.