Most mobile organisms respond to multiple cues when selecting habitat types,and laboratory experiments that manipulate only single cues may fail to reveal the true complexity of habitat-selection behaviour.In south-ea...Most mobile organisms respond to multiple cues when selecting habitat types,and laboratory experiments that manipulate only single cues may fail to reveal the true complexity of habitat-selection behaviour.In south-eastern Australia,broad-headed snakes Hoplocephalus bungaroides(Elapidae)lie in wait under sun-warmed rocks to ambush velvet geckos Oedura leseuerii(Gekkonidae).Previous laboratory work has shown that both the geckos and the snakes actively select hotter rather than colder rocks,and that the snakes actively select rocks scented by geckos.We manipulated rock temperature and the presence of two types of cues from geckos(chemical and visual information)to clarify the causal basis for foraging site selection by the juveniles of this snake.When given a choice between cold lizard-scented rocks and hot unscented rocks,our captive snakes gave a higher priority to lizard scent than to temperature.The snakes also selected shelter-sites that provided visual as well as scent cues from lizards,rather than shelter-sites with scent cues alone.Thus,although broad-headed snakes show a direct preference for hotter rather than colder rocks in the laboratory,their choice of foraging site in the field may also be influenced by the presence of scent cues from prey.Our laboratory results suggest that habitat selection by broad-headed snakes may be more complex than has been suggested by previous single-factor laboratory trials.展开更多
Bactericidal/permeability-increasing protein （BPI） and LPS-binding protein （LBP） play an important role in host defence. Current evidence shows that BPI/LBP may be widely existed in different cells and tissue type...Bactericidal/permeability-increasing protein （BPI） and LPS-binding protein （LBP） play an important role in host defence. Current evidence shows that BPI/LBP may be widely existed in different cells and tissue types of animals. A full-length cDNA clone encoding a BPI/LBP homologue （dBPI）, 1757 bp in size, was characterized in venom gland of the hundred-pace snake Deinagkistrodon acutus. Its deduced amino acid sequence of 417 residues had 13.8% - 21.5% identity to BPI like 1 （BPIL1） and BPI like 3 （BPIL3） of other animals. Conserved cysteine residues which are involved in disulfide bond formation between the final strand of the N-terminal beta sheet and the long alpha helix of BPI are identified as Cys146-Cys183 of dBPI. Phylogenetic tree analysis showed that the BPI/LBP homologues formed five large clusters and dBPI was in a large cluster including BPIL1 and BPIL3. dBPI mRNA shows a tissue specific expression in venom gland. This is the first study to identify the cDNA encoding BPI/LBP homologues from reptiles [ Current Zoology 55 （5） ： 376 - 382, 2009].展开更多
基金the University of Sydney,the Australian Research Council and the Bao's Foundation(China)for funding
文摘Most mobile organisms respond to multiple cues when selecting habitat types,and laboratory experiments that manipulate only single cues may fail to reveal the true complexity of habitat-selection behaviour.In south-eastern Australia,broad-headed snakes Hoplocephalus bungaroides(Elapidae)lie in wait under sun-warmed rocks to ambush velvet geckos Oedura leseuerii(Gekkonidae).Previous laboratory work has shown that both the geckos and the snakes actively select hotter rather than colder rocks,and that the snakes actively select rocks scented by geckos.We manipulated rock temperature and the presence of two types of cues from geckos(chemical and visual information)to clarify the causal basis for foraging site selection by the juveniles of this snake.When given a choice between cold lizard-scented rocks and hot unscented rocks,our captive snakes gave a higher priority to lizard scent than to temperature.The snakes also selected shelter-sites that provided visual as well as scent cues from lizards,rather than shelter-sites with scent cues alone.Thus,although broad-headed snakes show a direct preference for hotter rather than colder rocks in the laboratory,their choice of foraging site in the field may also be influenced by the presence of scent cues from prey.Our laboratory results suggest that habitat selection by broad-headed snakes may be more complex than has been suggested by previous single-factor laboratory trials.
基金funded by a grant from the local government of Zhejiang Province for the Specially Supported Discipline of Zoology
文摘Bactericidal/permeability-increasing protein （BPI） and LPS-binding protein （LBP） play an important role in host defence. Current evidence shows that BPI/LBP may be widely existed in different cells and tissue types of animals. A full-length cDNA clone encoding a BPI/LBP homologue （dBPI）, 1757 bp in size, was characterized in venom gland of the hundred-pace snake Deinagkistrodon acutus. Its deduced amino acid sequence of 417 residues had 13.8% - 21.5% identity to BPI like 1 （BPIL1） and BPI like 3 （BPIL3） of other animals. Conserved cysteine residues which are involved in disulfide bond formation between the final strand of the N-terminal beta sheet and the long alpha helix of BPI are identified as Cys146-Cys183 of dBPI. Phylogenetic tree analysis showed that the BPI/LBP homologues formed five large clusters and dBPI was in a large cluster including BPIL1 and BPIL3. dBPI mRNA shows a tissue specific expression in venom gland. This is the first study to identify the cDNA encoding BPI/LBP homologues from reptiles [ Current Zoology 55 （5） ： 376 - 382, 2009].
