"Evolutionary Insights: Nightmare Fish and the Origin of the Sympathetic Nervous System"
Lampreys, ancient jawless fish, were previously thought to lack a "fight or flight" response due to the absence of a structure called the neural crest. However, a new study published in Nature reveals that lampreys do have sympathetic nerve cells, suggesting that the vertebrate flight-or-flight response is more ancient than previously believed. This discovery sheds light on the evolution of this system and challenges previous assumptions about these primitive vertebrates.