image: American alligator (A. mississippiensis), hiding. At Rockefeller Wildlife Refuge. The ears of Alligators are hidden under skin flaps right behind the eyes. Alligators use sounds for communication and to locate prey. The neural mechanisms underlying sound localization are an evolutionary stable feature across archosaurs, which include birds, the closest living relatives to crocodilians. view more
Credit: Ruth Elsey, Louisiana Department of Wildlife and Fisheries
Alligators encode a sound's location in space like birds but differently than mammals, according to a comparative animal study published in JNeurosci. This finding provides evidence for the evolution of distinct strategies for spatial hearing.
To determine where a sound is coming from, animals glean information from how long it takes each ear to pick it up -- a cue known as interaural time difference. In their study of American alligators, Lutz Kettler (Technische Universität München) and Catherine Carr (University of Maryland, College Park) found the reptile's brain constructs neural maps to chart the location of a sound. Such maps have been observed in barn owls and chickens -- close relatives of the alligator -- but not in mammals. These differences suggest the common ancestor of reptiles and birds independently evolved the ability to localize sound.
###
Please contact media@sfn.org for full-text PDF: Neural maps of interaural time difference in the American alligator: a stable feature in modern archosaurs
About JNeurosci
JNeurosci, the Society for Neuroscience's first journal, was launched in 1981 as a means to communicate the findings of the highest quality neuroscience research to the growing field. Today, the journal remains committed to publishing cutting-edge neuroscience that will have an immediate and lasting scientific impact, while responding to authors' changing publishing needs, representing breadth of the field and diversity in authorship.
About The Society for Neuroscience
The Society for Neuroscience is the world's largest organization of scientists and physicians devoted to understanding the brain and nervous system. The nonprofit organization, founded in 1969, now has nearly 37,000 members in more than 90 countries and over 130 chapters worldwide.