Some of the media reports on our recently published paper in Behavioral Ecology, which experimentally demonstrated that the carotenoid-based frill of frillneck lizards is used to signal fighting ability.
Here’s our first paper on a reptile – the iconic Frillneck Lizard (Chlamydosaurus kingii). Both males and females have frills and until now, the consensus has always been that frills play a role in anti-predator behaviour. Not only does the frill startle a would-be predator, but it may also bluff them into thinking that their potential dinner might be dangerous and risky to catch. While this hypothesis still remains to be tested, together with the Martin Whiting from the Lizard Lab at Macquarie University, we explore an alternative hypothesis: that the frill might also play a role in sexual selection and signal fighting ability. We used optic spectrophotometry to objectively measure the colour of the frill and we also measured a range of morphological and functional traits before size matching lizards in staged contests in neutral arenas. Surprisingly, traits such as frill size, head size and bite force did not predict contest outcome. Instead, males with brighter and more colourful frills were more likely to dominate opponents and take gold. As an aside, we (well, Dave, actually) took skin samples back to the lab to determine the source of pigments that generate the colour. Lab tests confirmed the presence of carotenoids which is an exciting result because while carotenoids have been the source of considerable study among our feathered friends, we know little about the role of carotenoids in lizards (but see our lit cited for notable exceptions). To the best of our knowledge this is the first example of a carotenoid-based signal of fighting ability in a lizard. We will be continuing our study of colour polymorphism in frillneck lizards across the entire distribution…
Two new papers on the wild Gouldian finches are out this week – both led by past PhD student, James Brazill-Boast.One paper, published in Evolutionary Ecology, shows that wild red males defend higher-quality nest sites and suffered higher competition from both conspecifics and heterospecifics, but they also reared more fledglings than black males.
Another long-term study, published in Austral Ecology, shows that reproduction in wild Gouldian finches is limited by the availability of nest-sites, and that using artificial nest-boxes is an effective management tool for increasing both population densities and individual success in this endangered species.
While heading out early to one of the finch sites, a 2m freshwater crocodile was sighted by Cat Young (PhD student) and Fiona Finch (volunteer – and, yes, that is her real surname!) jumping from the division dam bridge in Kununurra into the lake. The photo (taken by Fi) made the front pages of the local newspaper, The Kimberley Echo.
Catherine Young has recently started a PhD looking at the relative costs and fitness benefits of aggression in a highly aggressive colonial-nesting bird – the crimson finch (also know as ‘red devils’ and ‘blood finches’ – and not just because of their fiery red coloration!).
Here’s a video by the Discovery Channel for their programme Ziyalogy, which illustrates (with some very cool animations!) that fear can be innate. It features some of our recent work on Gouldian finches showing that juveniles have innate fear of red. It’s pretty entertaining….
Some of the media reports on our recently published paper in Biology Letters, which experimentally demonstrated visual lateralization in mate choice. Gouldian finches appear to only use their right eye in selecting mates; when their right eye is covered (with a patch), birds are no longer able to reliably choose mates.
Right eye required for finding Mrs. Right – Science News
A field assistant is needed to help Catherine with a project investigating aggression in crimson finches. Field work will be conducted in the East Kimberley region of Western Australia from January to April 2013 (specific dates may vary). This is the wet season in the tropics and temperatures may reach 40oC with very high humidity. Volunteers will be involved with catching and banding birds, locating and monitoring nests, behavioural observations, re-sighting colour bands, habitat assessment and data entry. Continue reading Volunteer field assistant: Aggression in colonial finches
Several volunteers are needed to help Maddy with her PhD research on the tawny dragon lizard Ctenophorus decresii, a small agamid lizard. Male dragons found in the Flinders Ranges are seen in four different colour forms. She is investigating if colour types differ in ways additional to their colour and how such diversity is maintained within a population. The work involves catching the lizards, performing behavioural trials, estimating territory size and assessing physiological differences. Continue reading Field volunteer opportunity in the Flinders Ranges (SA)
A few of the media reports on our recently published paper in Proceedings of the Royal Society (Biological Sciences) that shows the huge stress responses of females that are constrained to breeding with incompatible (genetically dud males).
An article in the Kimberley Echo on the work by Honours student, Dhanya Pearce, who used stuffed Gouldian and long-tailed finches to look at aggression between the species over competition for nest sites. Continue reading Feathers fly in finch war
It seems that zebra finches are not only a model system for biologists – but are also an inspiration for artists. Recently Céleste Boursier-Mougenot presented a major new commission at The Barbican (London) to highlight how the rhythms of daily life can produce sound in unexpected ways. Continue reading Finch Rock ‘n Roll