“Everyone likes birds. What wild creature is more accessible to our eyes and ears, as close to us and everyone in the world, as universal as a bird?” - David Attenborough
We live in a colourful world. The colours of animals serve many functions from finding a mate to finding food. How and why has the animal world become so colourful?
To truly study animal colouration, we must consider what the world looks like to an animal. By peering through the eyes of nature, we can begin to understand the functions of animal colours.
“Nothing in biology makes sense except in the light of evolution” - Theodosius Dobzhansky
No facet of biodiversity is more striking than the resplendent variety of animal colouration. Thus, understanding the mechanisms and functions underlying this variety is pivotal to understanding biodiversity itself. For my PhD in the Stoddard Lab at Princeton I am investigating the ecology and evolution of plumage colouration in parrots, arguably the most social, vocal, intelligent and colourful birds.
A hypervolume is a multidimensional shape. Determining the geometry of such shapes can be a complicated task. Dr Benjamin Blonder has developed a new method for estimating the shape of a hypervolume, which employs kernel density estimation (read about it here). Under the supervision of Dr Blonder and Dr Joseph Tobias (my supervisor while I was a master’s student at Imperial College), I have been exploring the properties of the avian hypervolume, which is a trait/functional space since its axes are defined by traits or principal components of traits. On these spaces, each point represents the data for a single species. (on the graph to the left, the red represents real data and the blue is simulated).
In the case of the avian hypervolume, I am investigating whether the occupation density (number of points per unit volume) of the space is different near higher threat species than near lower threat species. This can help estimate the loss of unique function when extinction happens and possibly help identify species that might be of conservation importance.
Guppies have an extraordinary capacity to invade new environments. Native to Trinidad and north-east South America, guppies have now spread to every continent except Antarctica. My supervisor as the University of the West Indies, Dr Amy Deacon, has shown that a single female guppy is able to establish a mesocosm population that can survive two years (female guppies can store sperm once they’ve mated!). We are now investigating the colonising ability of ornamental and wild guppies.
I also carried out experiments that examined whether guppies are good mosquito control agents. I use guppies as a model system for behavioural experiments, looking at shoaling behaviour and the transmission of information between species.
For my undergraduate dissertation, I worked with Dr Julia Day and Dr Antonia Ford to test whether there were morphological differences among populations of a suckermouth catfish (Chiloglanis anoterus). Using geometric morphometrics, we found that significant morphological differences existed only among male tail morphologies for different populations. Combined with genetic data, this is an exciting example of sexual selection in the process of generating new species. (Publication here)