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Arlet Małgorzata E. Balasubramaniam Krishna N. Saha Rajarshi Beisner Brianne Marty Pascal R. Kaburu Stefano S. K. Bliss-Moreau Eliza Kaasik Ants Kodandaramaiah Ullasa McCowan Brenda 《International journal of primatology》2021,42(2):220-236
International Journal of Primatology - Female reproductive success depends to a large extent on infants’ ability to survive to maturity. While most studies of female reproductive success have... 相似文献
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The woody species richness patterns in three 2–4 km long transects, approximately 1–3 km apart in a lowland (600–700 m) dryland
around Lokapel in Turkana northern Kenya was analyzed in 2003 at 200–500 m intervals using the Point-Centred Quarter (PCQ)
method involving 51 observation points. Transect 1 and 2 were set along ephemeral runoff channels locally known as lagga with wet season flow westwards from the Lokapel Hills to the Turkwell River. Transect 3 was a cross-cutting profile dissecting
the area initially downhill from the Lokapel Hills and later gently uphill eastwards towards Lokichar. The altitude at each
of the 51 observation sites was recorded using a GPS and the woody species identified through local knowledge and taxonomic
aids. The results showed that the overall integrated altitudinal gradient for the three transects was approximately 100 m.
A total of 43 species of trees and shrubs were identified. The Shannon index showed that Transect 2 had the highest diversity
of woody species followed by Transect 1 and Transect 3 while the Sorensen’s index indicated qualitative dissimilarity between
all the transects. The results of regression analysis indicated that woody species richness increased linearly with elevation
in only one transect but regression analysis of height of woody plants and altitude indicated that only about 20% of the variation
in the height of woody plants was accountable by altitude. The spatial analysis of woody species-richness and altitudinal
gradient showed a dual peak pattern with the main richness peak in low lying areas below 700 m which was mainly within or
close to the riparian floodplain environment of the Turkwell River. A minor richness peak was also identified in higher lying
areas around the Lokapel hills. The species richness pattern was similar to the hump-shaped altitudinal species-richness pattern
which has been recorded widely around the world but mainly in large-scale studies. 相似文献
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Lauren J. Wooddell Stefano S. K. Kaburu Amanda M. Dettmer 《American journal of primatology》2020,82(11):e23024
Social network analysis is increasingly common in studying complex interactions among individuals. Across a range of primates, high-ranking adults are generally more socially connected, which results in better fitness outcomes. However, it still remains unclear whether this relationship between social network position and dominance rank emerges in infancy and whether, in species with a social transmission of dominance rank, social network positions are driven by the presence of the mother. To fill this gap, we first explored whether dominance ranks were related to social network position, measured via eigenvector centrality, in infants, juveniles, and adults in a troop of semi-free-ranging rhesus macaques (Macaca mulatta). We then examined relationships between dominance rank and eigenvector centrality in a peer-only group of yearlings who were reared with their mothers in either a rich, socially complex environment of multigenerational (MG) kin support or a unigenerational group of mothers and their infants from birth through 8 months. In Experiment 1, we found that mother's network position predicted offspring network position and that dominants across all age categories were more central in affiliative networks (social contact, social grooming, and social play). Experiment 2 showed that high-ranking yearlings in a peer-only group were more central only in the social contact network. Moreover, yearlings reared in a socially complex environment of MG kin support were more central. Our findings suggest that the relationship between dominance rank and social network position begins early in life, and that complex early social environments can promote later social competency. Our data add to the growing body of evidence that the presence/absence of the mother and kin influence how dominance rank affects social network position. These findings have important implications for the role of caregivers in the social status of developing primates, which ultimately ties to health and fitness outcomes. 相似文献
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In vitro anther-derived monoploids (2n=x=12) of Solanum phureja were compared for shoot regeneration from leaf and stem explants under various environmental conditions. Monoploids from the same or different diploid clones varied for frequency and earliness of shoot regeneration and number of shoots formed per explant. Leaf explants regenerated at higher frequencies than stem explants. Explants from stock plantlets subcultured at a 2- or 4-week interval regenerated earlier and at a higher frequency than those from plantlets subcultured at longer intervals. Regeneration frequency and number of shoots per explant were greater when explants were incubated at 20°C compared to 25°C. Explants from stock plantlets maintained under a 16 h as opposed to an 11 h photoperiod exhibited increased shoot regeneration; however, neither photoperiod nor the maintenance temperature of the stock plantlets influenced regeneration frequency. Genotypic differences were observed for the frequency of chromosome doubling among regenerated shoots whereas temperature treatments had no influence on chromosome doubling.Abbreviations BA
benzyladenine
- GA3
gibberellic acid
- IAA
indole-3-acetic acid
- NAA
-naphthale-neacetic acid 相似文献
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