| competition between tadpoles and mosquito larvae. | tadpoles and mosquito larvae often co-occur, and may compete for scarce resources. however, competition between such distantly related organisms has attracted less scientific attention than have interactions among closely related taxa. we examined ecological interactions in two tadpole-mosquito systems in southeastern australia, one from freshwater ponds (limnodynastes peronii and culex quinquefasciatus) and one from brackish-water habitats (crinia signifera and ochlerotatus australis). diets of ... | 2003 | 12684864 |
| ancient phylogeographic divergence in southeastern australia among populations of the widespread common froglet, crinia signifera. | geographic patterns of species diversity in southeast australia have been attributed to changes in pleistocene climate, but related phylogeographic patterns and processes are relatively understudied. 12s and 16s mitochondrial dna sequences in crinia signifera populations were used to infer historical patterns and processes in southeast australia. phylogenetic analysis identified three geographically restricted ancient lineages and several geographically restricted sub-clades. present-day feature ... | 2008 | 18348908 |
| reservoir-host amplification of disease impact in an endangered amphibian. | emerging wildlife pathogens are an increasing threat to biodiversity. one of the most serious wildlife diseases is chytridiomycosis, caused by the fungal pathogen, batrachochytrium dendrobatidis (bd), which has been documented in over 500 amphibian species. amphibians vary greatly in their susceptibility to bd; some species tolerate infection, whereas others experience rapid mortality. reservoir hosts-species that carry infection while maintaining high abundance but are rarely killed by disease- ... | 2016 | 27594575 |
| dynamics of chytridiomycosis during the breeding season in an australian alpine amphibian. | understanding disease dynamics during the breeding season of declining amphibian species will improve our understanding of how remnant populations persist with endemic infection, and will assist the development of management techniques to protect disease-threatened species from extinction. we monitored the endangered litoria verreauxii alpina (alpine treefrog) during the breeding season through capture-mark-recapture (cmr) studies in which we investigated the dynamics of chytridiomycosis in rela ... | 2015 | 26629993 |
| protamine-like sperm nuclear basic proteins in the primitive frog ascaphus truei and histone reversions among more advanced frogs. | sperm nuclear basic proteins (snbps) that condense chromatin are very diverse. in animals, evolution of snbps has proceeded from lysine-rich histone h type in sponges to more arginine-rich protamine-like pl and protamine p types. yet sporadic pl/p to h reversions are known to occur in both protostomes and deuterostomes. to determine why this is the case, we have examined snbps in eleven anuran species. we find that sperm of the primitive, internally fertilizing archeobatrachian frog a. truei (fa ... | 1999 | 10589504 |
| interspecific variation in the phenology of advertisement calling in a temperate australian frog community. | spatial and temporal partitioning of resources underlies the coexistence of species with similar niches. in communities of frogs and toads, the phenology of advertisement calling provides insights into temporal partitioning of reproductive effort and its implications for community dynamics. this study assessed the phenology of advertisement calling in an anuran community from melbourne, in southern australia. we collated data from 1432 surveys of 253 sites and used logistic regression to quantif ... | 2015 | 26442760 |
| environmental osmolality influences sperm motility activation in an anuran amphibian. | evolutionary theory predicts that selection will favour sperm traits that maximize fertilization success in local fertilization environments. in externally fertilizing species, osmolality of the fertilization medium is known to play a critical role in activating sperm motility, but there remains limited evidence for adaptive responses to local osmotic environments. in this study, we used a split-sample experimental design and computer-assisted sperm analysis to (i) determine the optimal medium o ... | 2015 | 25586700 |
| disulfide-containing peptides from the glandular skin secretions of froglets of the genus crinia: structure, activity and evolutionary trends. | the skin secretions of crinia signifera, c. riparia and c. deserticola contain bioactive disulfide-containing peptides. signiferin 1 (rlcipyiipc-oh) from c. signifera and c. deserticola) contracts smooth muscle at a concentration of 10(-9) m, and effects proliferation of lymphocytes at 10(-6) m. in contrast, riparin 1.1 (rlcipvifc-oh) and riparin 1.2 (flppcaykgtc-oh) from c. riparia show lymphocyte activity but do not contract smooth muscle. the lymphocyte and smooth muscle activities involve cc ... | 2008 | 18601958 |
| host-defence skin peptides of the australian common froglet crinia signifera: sequence determination using positive and negative ion electrospray mass spectra. | the amino acid sequences of seven signiferin peptides are provided by consideration of tandem mass spectrometric (ms/ms) data for the respective mh+ and [m--h]- precursor ions. these methods do not differentiate between isomeric residues leu and ile; these were identified using the edman degradation technique. the sequence of signiferin 1, a new smooth muscle contracting neuropeptide (rlcipyiipc-oh) containing a disulfide bridge, is best determined using the collision-induced dissociation (cid) ... | 2004 | 15317042 |
| ontogeny of bone and the role of heterochrony in the myobatrachine genera uperoleia, crinia, and pseudophryne (anura: leptodactylidae: myobatrachinae). | descriptive data are provided for ontogeny of bone to metamorphosis in the myobatrachine species uperoleia trachyderma; in pre- and postmetamorphic specimens of u. lithomoda, crinia signifera, and pseudophryne bibroni; and in postmetamorphic specimens of u. laevigata. data derived from postmetamorphic u. laevigata indicate that dermal and endochondral elements ossify independently of each other in uperoleia. crinia signifera does not show the same degree of independence of ossification of dermal ... | 1989 | 29865643 |