A finding stemming from Josiah's masters research was published today in Biology Letters! The paper, "Maternal provisioning interacts with incubation temperature to affect hatchling exposure in an oviparous reptile," reports on the interesting observation that incubation temperature affects how maternal resources (aka, the egg) are used by the embryo and in turn influences contaminant concentrations.
In some of our earlier work (See Bock et al., 2021 Biological Bulletin!) we found that cooler incubation temperatures produce smaller and less heavy hatchlings when compared to warmer temperatures. This finding held even after accounting for differences in the size of the egg, suggesting that at cooler temperatures hatchlings must expend more of their energy reserves to develop and having less left-over 'body.' But sometimes moms living in contaminated environments will deposit contaminants in their eggs (not on purpose), and as a result the embryos are exposed. When these maternally derived contaminants occur in cooler nests, they essentially "distill" or concentrate these samples into a smaller hatchling and lead to elevated contaminant concentrations. In alligators, these cooler temperatures produce females and thus females have higher contaminant burdens relative to their male siblings, even though they were both given the same amount of contaminants! Not cool. We still are unsure of if the difference is big enough to have an effect on individual health and likely depends on how much moms are depositing, but I'm sure more studies will come out of this. You can find a link to the paper here and if you lack access, feel free to email benparrott@srel.uga.edu and I can send you a PDF. |