Aardvarks (Orycteropus afer) are probably the most endearingly doofy-looking animals ever to grace the African continent. These Seussian snufflers look like someone threw an anteater, a rabbit, a pig and an armadillo into a smelter. Aardvarks have entered the consciousness of millions of children as both the first animal in any alphabetic listing, and the species ID of the titular character of the animated series Arthur. This all makes findings in a new paper published in the Royal Society journal Biology Letters particularly hard to hear: Climate change may kill off large numbers of aardvarks, to the point of regional extinction (or "extirpation") in many areas.
Image: Ewen Roberts/Flickr Creative Commons
Currently, aardvarks seem to be doing alright for themselves. They are found throughout much of sub-Saharan Africa, barring the hottest and driest parts. However, as climate change progresses, the areas that aardvarks live in are predicted to get hotter and drier, with longer and more frequent droughts. Considering aardvarks' avoidance of toasty, desert regions, the coming climatic shift is more than a little ominous for the species. A team of South African scientists studying the physiological flexibility of aardvarks received a glimpse into how this scenario could play out by tracking the body temperatures and movements of aardvarks during a brutally hot and dry summer -- conditions that closely replicate Africa's predicted future climate.
The researchers implanted sensors recording body temperature and physical activity ("biologgers") into six aardvarks inhabiting a semi-arid region of the Kalahari Desert in the winter of 2012. The aardvarks were released to go on their merry way for the next eight months, and the biologgers dutifully did what they were designed to do. What then followed was a summer of cruel extremes. Temperatures hit record highs and winds were a third stronger than normal, a combo that turned southern Africa into a blast furnace and induced severe drought conditions.
At the end of the summer, it came time to retrieve the biologgers. And how did the aardvarks do? Well, not great. All but one of the study aardvarks died, and nearly a dozen aardvarks at the site not a part of the study also perished. But data from the biologgers revealed that it likely wasn't heat stroke or dehydration that did them in. In the deceased aardvarks, body temperatures stayed relatively constant in the spring and start of the summer, but declined overall as the summer progressed, swinging extremely low at night. The normally nocturnal animals also flipped their schedules, becoming active during the day. This, coupled with the fact that all the study aardvarks were found emaciated, suggests that the aardvarks actually starved to death.
Without adequate ants and termites -- which need a minimum level of soil moisture to survive -- the aardvarks ran low on energy reserves, unable to maintain their core temperatures and resorting to braving the hot sun just to keep all systems running. Until they couldn't any more.
The study provides a grim peek into the future for aardvarks. Largely incapable of surviving the indirect effects of conditions that are expected to be commonplace in the coming century, aardvarks may vanish from vast swaths of their current range, or even risk extinction. Worse still, the loss of aardvarks could trigger a domino effect for African ecosystems. Aardvarks, with their constant burrowing and excavating, are "ecosystem engineers", modifying the physical environment in a way that creates shelter and resources for scores of other creatures. Beavers do it when they dam waterways, for example. The loss of these types of engineers in places such as Australia has already been shown to damage ecosystems. There are many lifeforms that stand to lose from the disaster that is drought-induced aardvark starvation, preschoolers learning their ABC's and meme makers just some of them.
If Africa continues to heat up and dry out, as is expected in future decades, less and less territory will be suitable for aardvarks, and their range will substantially shrink. While it is possible some regions that were previously too swampy and waterlogged for aardvarks to successfully inhabit could become hospitable as they dried out, it would come at a loss of other ecosystems, and aardvarks would still have a greatly diminished presence on the continent as former grasslands transition to deserts. The widespread loss of aardvarks is not entirely destiny, but their survival largely depends on humanity addressing climate change.