Sharks longing for home:
Lemon sharks remember where they were born.  Yes, sharks get born.  They don’t lay eggs.  It’s something to do with the fact that most sharks have to swim to aerate their gills – basking sharks excepted – and eggs swim poorly.  And they remember the event.  (Sharks Never Forget Home NATURE vol. 504 no. 7478 December 5, 2013 page 10 reviewing work led by Kevin Feldheim of the Chicago Field Museum and reported as Mol. Ecol. They observed that female lemon sharks return to where they were born in order themselves to give birth.  So far as that goes the first thing that comes to mind, as the authors point out, is that such areas ought to get special attention for protection, ditto nursery areas for the sharks, which have a similar draw.

Of course I can’t leave it at that.  I mean it makes good sense that a place that proved suitable in the past should have a better chance than others of proving suitable in the future.  But what about the males?  Do they return as well?  Do they make trysts with females born in the same areas or raised in the same nurseries?  If so, that would be yet another pebble on the mountain of evidence that animals seek to mate with kin.

There have been 52 visitors over the past month.

Home page