A note on the structure of tail hairs from a pygmy hippopotamus (Choeropsis liberiensis)

The pygmy hippopotamus (Choeropsis liberiensis), like the Nile hippopotamus (Hippopotamus amphibius), defecates by backing into vertical objects while making a series of rapid, propellerlike tail movements that spread a mixture of urine and feces in a wide swath. Split hairs from the distal ventral surface of the pygmy hippopotamus tail were studied with the scanning electron microscope to determine whether the splitting was a normal character of the hair or was due to damage. The results suggest that splitting is a normal feature of the hair that may facilitate the dispersal of urine and feces.     

Climate change and perishable food hoards of an avian predator: Is the freezer still working?

Changing climate can modify predator–prey interactions and induce declines or local extinctions of species due to reductions in food availability. Species hoarding perishable food for overwinter survival, like predators, are predicted to be particularly susceptible to increasing temperatures. We analysed the influence of autumn and winter weather, and abundance of main prey (voles), on the food‐hoarding behaviour of a generalist predator, the Eurasian pygmy owl (Glaucidium passerinum), across 16 years in Finland. Fewer freeze–thaw events in early autumn delayed the initiation of food hoarding. Pygmy owls consumed more hoarded food with more frequent freeze–thaw events and deeper snow cover in autumn and in winter, and lower precipitation in winter. In autumn, the rotting of food hoards increased with precipitation. Hoards already present in early autumn were much more likely to rot than the ones initiated in late autumn. Rotten food hoards were used more in years of low food abundance than in years of high food abundance. Having rotten food hoards in autumn resulted in a lower future recapture probability of female owls. These results indicate that pygmy owls might be partly able to adapt to climate change by delaying food hoarding, but changes in the snow cover, precipitation and frequency of freeze–thaw events might impair their foraging and ultimately decrease local overwinter survival. Long‐term trends and future predictions, therefore, suggest that impacts of climate change on wintering food‐hoarding species could be substantial, because their ‘freezers’ may no longer work properly. Altered usability and poorer quality of hoarded food may further modify the foraging needs of food‐hoarding predators and thus their overall predation pressure on prey species. This raises concerns about the impacts of climate change on boreal food webs, in which ecological interactions have evolved under cold winter conditions.     

Association between pygmy right whales (Caperea marginata) and areas of high marine productivity off Australia and New Zealand

Abstract

Opportunistic sightings and strandings of Caperea marginata (n=196) from the vicinity of Australia and New Zealand (1884 to early 2007) were used to relate geographic and temporal patterns to oceanographic and broad-scale climatic variability. Records were not uniformly distributed along the coast and more (69%) were from Australia than New Zealand. Seven coastal whale ‘hotspots’ were identified which accounted for 61% of records with locality data. Half of the hotspot records were from southeast (37) and northwest (20) Tasmania—others each had 9–15 events. Upwelling and/or high zooplankton abundance has been documented near all whale hotspots. Records of C. marginata occurred in all months, with 75% in spring and summer. Inter-annual variability showed broad agreement between increased whale records (usually in spring/summer) and strongly positive ‘Niño 3.4’ during 1980–1995 but not thereafter. Coastal upwelling and productivity increase during climatic phenomena such as El Niño and are likely to be quickly beneficial to plankton-feeding whales such as C. marginata.     

Phylogenetic analysis of the fecal flora of the wild pygmy loris

The bacterial diversity in fecal samples from the wild pygmy loris was examined with a 16S rDNA clone library and restriction fragment length polymorphism analysis. The clones were classified as Firmicutes (43.1%), Proteobacteria (34.5%), Actinobacteria (5.2%), and Bacteroidetes (17.2%). The 58 different kinds of 16S rDNA sequences were classified into 16 genera and 20 uncultured bacteria. According to phylogenetic analysis, the major genera within the Proteobacteria was Pseudomonas, comprising 13.79% of the analyzed clone sequences. Many of the isolated rDNA sequences did not correspond to known microorganisms, but had high homology to uncultured clones found in human feces. Am. J. Primatol. 72:699–706, 2010. © 2010 Wiley‐Liss, Inc.     

Status of the so-called African pygmy elephant (Loxodonta pumilio (NOACK 1906)): phylogeny of cytochrome b and mitochondrial control region sequences

Among the African elephants, it has been unanimously acknowledged that the forest elephants (cyclotis form) are peculiar, so that they have been elevated to the specific rank. The development of molecular analyses of extant Loxodonta has only focused on two forms yet: the savannah form (africana) and the forest form (cyclotis), disregarding the so-called pygmy elephants (pumilio or fransseni) the systematic status of which has been debated since their discovery. Therefore, we have sampled nine dwarfed-labelled specimens in collection and eight specimens of typical forest elephants that we compared to three savannah elephants and two Asian elephants. Because of the degraded nature of the nuclear DNA content in bone samples of old specimens, we assayed mitochondrial markers; 1961 bp of the mitochondrial genome were sequenced (over a continuous range spanning the cytochrome b gene, tRNA Thr, tRNA Pro, hypervariable region 1 and central conserved region of the control region). Pumilio and cyclotis are not sister-taxa: the phylogenetic analyses rather account for the inclusion of the so-called pygmy elephants within a monophyletic group of forest elephants sensu lato. The internal structure of this clade reveals to depend on isolation and remoteness between populations, characteristics that may have been extensively influenced by climatic variations during the Quaternary period. We conclude that the specific taxon Loxodonta pumilio (or Loxodonta fransseni) should be abandoned.     

Markers of physiological stress in juvenile bonobos (Pan paniscus): Are enamel hypoplasia,skeletal development and tooth size interrelated?

A reduction in enamel thickness due to disrupted amelogenesis is referred to as enamel hypoplasia (EH). Linear EH in permanent teeth is a widely accepted marker of systemic physiological stress. An enigmatic, nonlinear form of EH commonly manifest in great ape and human deciduous canines (dc) is known as localized hypoplasia of primary canines (LHPC). The etiology of LHPC and what it signifies—localized traumatic or systemic physiological stress—remains unclear. This report presents frequency data on LHPC, hypostotic cranial traits, and tooth size in a sample of juvenile bonobos, then tests hypotheses of intertrait association that improve knowledge of the etiology and meaning of LHPC. The fenestration hypothesis is tested using hypostotic cranial traits as a proxy for membrane bone ossification, and the relationship between tooth size, LHPC, and hypostosis is investigated. Macroscopic observations of EH, hypostotic traits, and measurements of buccolingual tooth size were conducted according to established standards. LHPC was found in 51.2% of bonobos (n = 86) and in 26% of dc teeth (n = 269). Hypostotic traits were observed in 55.2% of bonobos (n = 96). A test of the association between LHPC and hypostosis yielded nonsignificant results (χ² = 2.935; P = 0.0867). Primary canines were larger in specimens with LHPC than in unaffected specimens (paired samples t test; udc, P = 0.011; ldc, P = 0.018), a result consistent with the fenestration hypothesis of LHPC pathogenesis. Hypostosis was not associated with differences in tooth size (P > 0.05). LHPC may be an indirect indicator of physiological stress, resulting from large, buccally displaced primary canines. Am J Phys Anthropol, 2009. © 2008 Wiley‐Liss, Inc.     

Past and present distribution, densities and movements of blue whales Balaenoptera musculus in the Southern Hemisphere and northern Indian Ocean

• 1 Blue whale locations in the Southern Hemisphere and northern Indian Ocean were obtained from catches (303 239), sightings (4383 records of ≥8058 whales), strandings (103), Discovery marks (2191) and recoveries (95), and acoustic recordings.
• 2 Sighting surveys included 7 480 450 km of effort plus 14 676 days with unmeasured effort. Groups usually consisted of solitary whales (65.2%) or pairs (24.6%); larger feeding aggregations of unassociated individuals were only rarely observed. Sighting rates (groups per 1000 km from many platform types) varied by four orders of magnitude and were lowest in the waters of Brazil, South Africa, the eastern tropical Pacific, Antarctica and South Georgia; higher in the Subantarctic and Peru; and highest around Indonesia, Sri Lanka, Chile, southern Australia and south of Madagascar.
• 3 Blue whales avoid the oligotrophic central gyres of the Indian, Pacific and Atlantic Oceans, but are more common where phytoplankton densities are high, and where there are dynamic oceanographic processes like upwelling and frontal meandering.
• 4 Compared with historical catches, the Antarctic (‘true’) subspecies is exceedingly rare and usually concentrated closer to the summer pack ice. In summer they are found throughout the Antarctic; in winter they migrate to southern Africa (although recent sightings there are rare) and to other northerly locations (based on acoustics), although some overwinter in the Antarctic.
• 5 Pygmy blue whales are found around the Indian Ocean and from southern Australia to New Zealand. At least four groupings are evident: northern Indian Ocean, from Madagascar to the Subantarctic, Indonesia to western and southern Australia, and from New Zealand northwards to the equator. Sighting rates are typically much higher than for Antarctic blue whales.
• 6 South‐east Pacific blue whales have a discrete distribution and high sighting rates compared with the Antarctic. Further work is needed to clarify their subspecific status given their distinctive genetics, acoustics and length frequencies.
• 7 Antarctic blue whales numbered 1700 (95% Bayesian interval 860–2900) in 1996 (less than 1% of original levels), but are increasing at 7.3% per annum (95% Bayesian interval 1.4–11.6%). The status of other populations in the Southern Hemisphere and northern Indian Ocean is unknown because few abundance estimates are available, but higher recent sighting rates suggest that they are less depleted than Antarctic blue whales.

     

Molecular Evolution of Prolactin in Primates

Pituitary prolactin, like growth hormone (GH) and several other protein hormones, shows an episodic pattern of molecular evolution in which sustained bursts of rapid change contrast with long periods of slow evolution. A period of rapid change occurred in the evolution of prolactin in primates, leading to marked sequence differences between human prolactin and that of nonprimate mammals. We have defined this burst more precisely by sequencing the coding regions of prolactin genes for a prosimian, the slow loris (Nycticebus pygmaeus), and a New World monkey, the marmoset (Callithrix jacchus). Slow loris prolactin is very similar in sequence to pig prolactin, so the episode of rapid change occurred during primate evolution, after the separation of lines leading to prosimians and higher primates. Marmoset prolactin is similar in sequence to human prolactin, so the accelerated evolution occurred before divergence of New World monkeys and Old World monkeys/apes. The burst of change was confined largely to coding sequence (nonsynonymous sites) for mature prolactin and is not marked in other components of the gene sequence. This and the observations that (1) there was no apparent loss of function during the episode of rapid evolution, (2) the rate of evolution slowed toward the basal rate after this burst, and (3) the distribution of substitutions in the prolactin molecule is very uneven support the idea that this episode of rapid change was due to positive adaptive selection. In the slow loris and marmoset there is no evidence for duplication of the prolactin gene, and evidence from another New World monkey (Cebus albifrons) and from the chimpanzee and human genome sequences, suggests that this is the general position in primates, contrasting with the situation for GH genes. The chimpanzee prolactin sequence differs from that of human at two residues and comparison of human and chimpanzee prolactin gene sequences suggests that noncoding regions associated with regulating expression may be evolving differently from other noncoding regions.     

Chromosome painting between human and lorisiform prosimians: evidence for the HSA 7/16 synteny in the primate ancestral karyotype

Multidirectional chromosome painting with probes derived from flow-sorted chromosomes of humans (Homo sapiens, HSA, 2n = 46) and galagos (Galago moholi, GMO, 2n = 38) allowed us to map evolutionarily conserved chromosomal segments among humans, galagos, and slow lorises (Nycticebus coucang, NCO, 2n = 50). In total, the 22 human autosomal painting probes detected 40 homologous chromosomal segments in the slow loris genome. The genome of the slow loris contains 16 sytenic associations of human homologues. The ancient syntenic associations of human chromosomes such as HSA 3/21, 7/16, 12/22 (twice), and 14/15, reported in most mammalian species, were also present in the slow loris genome. Six associations (HSA 1a/19a, 2a/12a, 6a/14b, 7a/12c, 9/15b, and 10a/19b) were shared by the slow loris and galago. Five associations (HSA 1b/6b, 4a/5a, 11b/15a, 12b/19b, and 15b/16b) were unique to the slow loris. In contrast, 30 homologous chromosome segments were identified in the slow loris genome when using galago chromosome painting probes. The data showed that the karyotypic differences between these two species were mainly due to Robertsonian translocations. Reverse painting, using galago painting probes onto human chromosomes, confirmed most of the chromosome homologies between humans and galagos established previously, and documented the HSA 7/16 association in galagos, which was not reported previously. The presence of the HSA 7/16 association in the slow loris and galago suggests that the 7/16 association is an ancestral synteny for primates. Based on our results and the published homology maps between humans and other primate species, we propose an ancestral karyotype (2n = 60) for lorisiform primates.