Holy F’n 2-Headed Shark Batman!

Screen Shot 2013-03-26 at 7.53.46 PMWell I just found new fodder for my nightmares. The two-headed fetus was removed from a pregnant female captured in the Gulf of Mexico near Key West, Florida, U.S.A. by a commercial fishing vessel (F/V Island Girl) on 7 April 2011.  According to the authors of the recent study describing this anomaly.

Each head has five pairs of gills and gill openings, a single pair of eyes, a single pair of nares and a mouth with well-developed dentition. The teeth appear both normally formed.

Apparently, dicephalia (two-headed) is rare in sharks (or rarely reported anyway).  Besides the bullshark here, previous reports include the Squalus acanthias, longnose spurdog Squalus blainville, milk shark Rhizoprionodon acutus, blue shark Prionace glauca, and the tope shark Galeorhinus galeus. Total hat tip to David Shiffman, aka Mr. Shark, aka purveyor of weird, aka moncephalic scientists, aka @whysharksmatter Screen Shot 2013-03-26 at 7.53.54 PM

C. M. Wagner, P. H. Rice and A. P. Pease First record of dicephalia in a bull shark Carcharhinus leucas (Chondrichthyes: Carcharhinidae) foetus from the Gulf of Mexico, U.S.A. Journal of Fish Biology 25 MAR 2013 | DOI: 10.1111/jfb.12064

Dr. M (1729 Posts)

Craig McClain is the Assistant Director of Science for the National Evolutionary Synthesis Center, a National Science Foundation supported initiative. He has conducted deep-sea research for 20 years and published over 50 papers in the area. He has participated in and led dozens of oceanographic expeditions taken him to the Antarctic and the most remote regions of the Pacific and Atlantic. Craig’s research focuses on how energy drives the biology of marine invertebrates from individuals to ecosystems, specifically, seeking to uncover how organisms are adapted to different levels of carbon availability, i.e. food, and how this determines the kinds and number of species in different parts of the oceans. Craig’s research has been featured on National Public Radio, Discovery Channel, Fox News, National Geographic and ABC News. In addition to his scientific research, Craig also advocates the need for scientists to connect with the public and is the founder and chief editor of the acclaimed Deep-Sea News (http://deepseanews.com/), a popular ocean-themed blog that has won numerous awards. His writing has been featured in Cosmos, Science Illustrated, American Scientist, Wired, Mental Floss, and the Open Lab: The Best Science Writing on the Web. His forthcoming book, Science of the South (http://www.scienceofthesouth.com/), connects cultural icons of South such as pecan pie with the science behind them.