The Jonah crab, Cancer borealis, is found all along the Eastern coast of the U.S. and at various depths and water temperatures. As an ectotherm, this animal cannot regulate its body temperature and therefore the temperature of the surrounding water can affect its physiology and behavior.

But have you ever wondered if a species seeks out or avoids a particular temperature to optimize a physiological character? In a recent study published in the Journal of Experimental Marine Biology and Ecology, Lara Lewis, a graduate student in Joseph Ayers’ lab, examined the behaviors of the Jonah crab in a thermal gradient tank to see how they react when placed at various temperatures.

Lewis discovered that the crabs do move towards a preferred temperature range, which is significantly impacted by their previous acclimation temperature.  The Jonah crab is often studied as a model species, and is also an economically valuable fishery, which is why it is important to understand its thermoregulatory behavior in the face of variable – and warming – sea temperatures. Lewis also found that, in all cases, the crab preferred temperatures warmer than those where it had previously been living.