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In the modern definition of adaptive radiation, a clade rapidly diversifies from a common ancestor to colonize a wide variety of new ecological niches. The idea of multiplication of species related to an adaptive radiation is well accepted. However, the assessment of how ecological and phenotypic diversity is interrelated in the case of adaptive radiation has rarely been studied. This is the background of the present paper, which aimed to test the correlation between phenotypic disparity and the rate of morphological evolution in relationship to ecological diversity in terrestrial Carnivora. To do so, we used geometric morphometrics to investigate skull shape disparity and the rate of morphological evolution at the family level in Carnivora. Our analyses highlight a correlation between ecological diversity and phenotypic disparity and demonstrate that the skull shape is impacted by ecology. On the contrary, our data do not provide any correlation between ecological diversity and the rate of morphological evolution, nor between phenotypic disparity and the rate of morphological evolution. We suggest that this absence of correlation could be explained by a contrasting tempo and a shift in morphological evolutionary rate among families. [ABSTRACT FROM AUTHOR]

The Boh Dambang karstic site in southern Cambodia, Kampot province, is a mammal bone-rich deposit in a hyena site. Very few hyena sites have been recovered in the Pleistocene of Southeast Asia, thus little information is known about the foraging abilities of hyenas during that period and their decline in the region, while the other hypercarnivores (tiger, leopard, and dhole) persisted until present day. To constrain the site we applied luminescence (red TL and single-grain OSL), ESR and U/Th dating methods to the sediments and faunal teeth, respectively. The resulting age estimates suggest that the site represents an accumulation of a young deposit with faunal teeth in the range of 25–18 ka that was last exposed to sunlight between 8 and 7 ka, and an older deposit containing older teeth (∼100–80 ka) that have been eroded from the upper caves in the system and incorporated into the younger deposit. Thus, the faunal age of 25–18 ka (MIS2), provides the best estimate for the age of the hyena site during LGM (26.5–19 ka). We analysed the assemblage of isolated teeth in terms of taxonomic diversity and abundance. The role of bone accumulators, either carnivores or rodents, has been precised through a taphonomic analysis. Diet was reconstructed through measurement of δ 13 C values of tooth enamel. The taphonomic analysis reveals that the hyenas were the main bone accumulators at Boh Dambang. Porcupines were aslo a factor in the accumulation of remains. The results show that the spotted hyenas hunted large-sized herbivores (>600 kg), in a mixed environment dominated by grassland. These data along with evidence from other Pleistocene faunas from Southeast Asian mainland, in terms of prey preference of hyenas (“rhinoceroses versus large bovines”) also reveal marked differences in relation to habitat type. Possible causes of the decline of the spotted hyena in the Indochinese sub-region (hypercarnivory, high trophic level, comparable foraging strategies with hunters-gatherers, and climatic changes) are tentatively proposed at this point. [ABSTRACT FROM AUTHOR]

Karstic sites have great potential for yielding data regarding changes in faunal communities in the Pleistocene of Southeast Asia. In this region, the majority of fossil-bearing deposits are karstic breccias, which generally demonstrate a complicated sedimentary history. While most of the mammalian assemblages recovered in these deposits are only composed of isolated teeth, their study remains essential for reconstructing paleoecology and paleoclimatology of the region. We analyzed the assemblages recovered in three mainland and two insular karstic sites: Tam Hang South and Nam Lot in northern Laos, Duoi U'Oi in northern Vietnam, Punung in central Java and Sibrambang in western Sumatra and obtained new chronologies for three of these sites so that their significance could be discussed within their correct chronological context. The resulting age ranges place the sites in MIS5 and MIS4. The comparative analysis of the faunas, in terms of taphonomy, taxonomic diversity and abundance, and mortality profiles ( Cervus unicolor , Sus scrofa , Sus vittatus , rhinocerotids and Tapirus indicus ), reveals marked differences in prey–predators (carnivores and/or humans) relationships in relation to habitat. The study of hominines-bearing sites (Punung, Nam Lot, Duoi U'Oi) allows us to emphasize different interactions with large carnivores (felids, hyaenids, canids). [ABSTRACT FROM AUTHOR]

In primate species, mating decisions seem to be based on multiple signal elements with different roles in the signaling of female reproductive status. Whereas some primate signals are relatively well described (e.g., sexual swellings and copulation calls), studies that simultaneously assess visual, auditory, behavioral, and olfactory cues as signals of reproductive state are rarely undertaken. We used data on variation in sexual behaviors and sexual swellings in relation to the fertile period (estimated from the date of swelling detumescence) from a troop of semi-free ranging olive baboons ( Papio anubis) to assess how different signals influence patterns of mate choice. Using an objective and quantitative measure of swelling size and color, along with detailed data on sexual behaviors from 13 cycles of nine adult females, we found that fine-scale variation in sexual swelling size, female behavior and copulation call rates could advertise the beginning of the fertile phase whereas swelling color did not. Rates of olfactory inspections by males also increased during the fertile phase, suggesting that olfactory signals were of interest to males and may contain information about ovulation. There was no relationship between female characteristics (age and rank) and the expression of sexual signals, except for proceptive behaviors which increased with female rank. Males displayed more sexual behaviors such as approaches and holding and tended to direct more ejaculatory mounts during the fertile phase. All together, we suggest that whereas all males could have information concerning the timing of ovulation through female proceptive behaviors and swelling size, consorting males may have access to additional signals (olfactory cues). Sexual communication in olive baboons is consistent with a multimodal framework for fertility signaling, potentially allowing males and females to establish different mating strategies. The possible selective pressures leading to multi-modal signaling are discussed. Am. J. Primatol. 75:774-787, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]