Capital Breeding in Cooler Cape Town
A new study suggests that guttural toads are changing their breeding patterns to accommodate the cooler, drier Cape Town climate.
In this study, Giovanni Vimercati compared the mass of different organs from guttural toads from their native population in Durban (see post here) and the invasive population in the peri urban area of Constantia, near Cape Town. The relative masses of the different organs provide information about how these toads invest their energy.
Native frogs in Cape Town save up much more energy in their storage organs prior to breeding, because of the inhospitable dry summers. Whereas the guttural toad in its native Durban, uses energy as they generate it during the breeding period. These two strategies are known as capital- and income-breeding, respectively.
Giovanni's study suggests that even though they have only been in Cape Town for less than 20 years, they have already started moving toward a capital breeding strategy, typical of the native species in the area. However, he only found this difference in females and not males.
The MeaseyLab is conducting lots of interesting work on invasive populations of Guttural Toads at the moment. To see more blog posts about this work, click here.
Vimercati, G., Davies, S. & Measey, J. (2019) Invasive toads adopt marked capital breeding when introduced to a cooler, more seasonal environment. Biological Journal of the Linnnean Societyhttps://doi.org/10.1093/biolinnean/blz119 pdf
