CHANGES IN THE DEMOGRAPHIC TRENDS OF PINK RIVER DOLPHINS (INIA) AT THE MICROGEOGRAPHICAL LEVEL IN PERUVIAN AND BOLIVIAN RIVERS AND WITHIN THE UPPER AMAZON:MICROSATELLITES AND MTDNA ANALYSES AND INSIGHTS INTO INIA’S ORIGIN - Biology, Evolution and Conservation of River Dolphins Within South America and Asia - page 174

The k and g tests of Goldstein et al. (1998) did not detect any expansion trend in all the
populations analyzed (Table 3). The only case where the statistical level was borderline to the
significance was for the Napo-Curaray rivers, where the k test (p = 0.075) indicated a possible
population expansion. Thus, both of these tests did not reveal significant population changes
in the population analyzed. This reveals that, in the condition of the present analysis, these
tests were less powerful in detecting changes in any population trend compared to tests by
Kimmel et al. (1998) and Zhivotovsky et al. (2000).
mtDNA
The overall Amazon sequence set showed levels of gene diversity considerably higher
than the Bolivian sequence set ( = 0.0116 and  per gene = 4.646 versus  = 0.0014 and 
per gene = 0.5789, respectively). This means that the Amazon set has eight times more gene
diversity than the Bolivian sample. Within the Amazon sample, the Peruvian rivers showed
the highest gene diversity statistics, all of them being very similar, [ = 0.0164 and  per gene
= 6.549 (Ucayali river),  = 0.0150 and  per gene = 6.000 (Marañón river),  = 0.0175 and 
per gene = 7.003 (Napo-Curaray rivers)], whereas the dolphin populations from the two
Colombian rivers yielded lower gene diversity levels, especially the Putumayo River ( =
0.0022 and  per gene = 0.8961, Colombian Putumayo River, and  = 0.0048 and  per gene
= 1.907, Colombian Caquetá River).
The mismatch distribution (pairwise sequence differences) and their respective associated
statistics ( rg , MAE and the R 2 statistic) as well as the Fu and Li D and F tests and the Fu F S
and the Tajima D showed some demographic trend in the following pink river dolphin
ensembles (Table 4): In the Ucayali River, the Fu & Li D* test revealed a significant
bottleneck event (95 % confidence interval, -2.227; 1.331, with p[D* < 1.358] = 0.021) as
well as the same was detected for the Napo-Curaray rivers with the same test (95 %
confidence interval, -2.449; 1.353, with p[D* < 1.306] = 0.033). But the unique case that
revealed a clear population expansion was the pink river dolphin ensemble constituted by the
overall Amazon sample. The vast majority of the tests yielded striking evidence of an
important population expansion (R2: 95 % confidence interval, 0.041; 0.153, with p[R2 <
0.0439] = 0.038; D*: 95 % confidence interval, -2.255; 1.563, with p[D* < -2.707] = 0.014;
F*: 95 % confidence interval, -2.208; 1.753, with p[F* < -2.906] = 0.009; D: 95 % confidence
interval, -1.609; 1.896, with p[D < -2.037] = 0.002) (Figure 1). The remaining ensembles
(Marañón River, all the Peruvian rivers taken together, Bolivia) as well as the remaining tests
for the Ucayali and the Napo-Curaray rivers showed stable female lineage populations.