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您的检索式：作者名="Robyn S.HETEM"
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| 1 | Body temperature,activity patterns and hunting in free-living cheetah:biologging reveals new insights显示文摘As one of the few felids that is predominantly diurnal,cheetahs(Acinonyx jubatus)can be exposed to high heat loads in their natural habitat.Little is known about long-term patterns of body temperature and activity(including hunting)in cheetahs because long-term concurrent measurements of body temperature and activity have never been reported for cheetahs,or,indeed,for any free-living felid.We report here body temperature and locomo-tor activity measured with implanted data loggers over 7 months in 5 free-living cheetahs in Namibia.Air tem-perature ranged from a maximum of 39°C in summer to−2°C in winter.Cheetahs had higher(~0.4°C)max-imum 24-h body temperatures,later acrophase(~1 h),with larger fluctuations in the range of the 24-h body temperature rhythm(approximately 0.4°C)during a hot-dry period than during a cool-dry period,but main-tained homeothermy irrespective of the climatic conditions.As ambient temperatures increased,the cheetahs shifted from a diurnal to a crepuscular activity pattern,with reduced activity between 900 and 1500 hours and increased nocturnal activity.The timing of hunts followed the general pattern of activity;the cheetahs hunted when they were on the move.Cheetahs hunted if an opportunity presented itself;on occasion they hunted in the midday heat or in total darkness(new moon).Biologging revealed insights into cheetah biology that are not ac-cessible by traditional observer-based techniques. | Robyn S.HETEM Duncan MITCHELL Brenda A.DE WITT Linda G.FICK Shane K.MALONEY Leith C.R.MEYER and Andrea FULLER | 2019 | Integrative Zoology2019，14，1： | 0 |
| 2 | Stable isotope analysis of diet confirms niche separation of two sympatric species of Namib Desert lizard显示文摘We used stable isotopes of carbon and nitrogen to study the trophic niche of two species of insectivorous lizards,the Husab sand lizard Pedioplanis husabensis and Bradfield’s Namib day gecko living sympatrically in the Namib Desert.We measured theδ13C andδ15N ratios in lizard blood tissues with different turnover times(whole blood,red blood cells and plasma)to investigate lizard diet in different seasons.We also measured theδ13C andδ15N ratios in available arthropod prey and plant tissues on the site,to identify the avenues of nutrient movement between lizards and their prey.Through the use of stable isotope mixing models,we found that the two lizard species relied on a largely non-overlapping but seasonally variable array of arthropods:P.husabensis primarily fed on termites,beetles and wasps,while R.bradfieldi fed mainly on ants,wasps and hemipterans.Nutrients originating from C3 plants were proportionally higher for R.bradfieldi than for P.husabensis during autumn and late autumn/early winter,although not summer.Contrary to the few available data estimating the trophic transfer of nutrients in ectotherms in mixed C3 and C4/crassulacean acid metabolism(CAM)plant landscapes,we found that our lizard species primarily acquired nutrients that originated from C4/CAM plants.This work adds an important dimension to the general lack of studies using stable isotope analyses to estimate lizard niche partitioning and resource use. | Ian W.MURRAY Hilary M.LEASE Robyn S.HETEM Duncan MITCHELL Andrea FULLER Stephan WOODBORNE | 2016 | Integrative Zoology2016，11，1： | 0 |
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