Hybrid Sharks and Other News of the Week
Blacktip Reef Shark (Image by warrenski via Flickr)
This week finds us enthralled by the many flavors of evolutionary adaptation.
Yesterday The Four-Year-Old and I learned that scientists have discovered not one, not two, but 57 hybrid sharks swimming off the coast of Australia. The hybrids are the result of interbreeding between two relatively similar species: the common blacktip shark and the Australian blacktip shark.
According to James Cook University Professor Colin Simpfendorfer, scientists don’t yet know why the two species have suddenly begun interbreeding. It could be a response to overfishing, to climate change, or simply what happens when an Australian blacktip shark and a common blacktip shark swim in the same waters for a change (normally the Australian blacktip shark swims in the tropical waters near Brisbane, while the common blacktip prefers the cooler waters off Sydney). Regardless, Simpfendorfer thinks the hybridization may give these sharks an evolutionary advantage by giving them more flexibility to adapt to ongoing climate change.
And then there’s the rather remarkable octopus, a species that can edit their RNA in response to external cues, such as the temperature of the water around them–enabling them to thrive even under what ought to be hostile conditions.
And finally, although it doesn’t necessarily fall under the rubrik of interesting adaptations, I was lucky enough to run across a fascinating neuroscience blog this week called A Hippo on Campus. Topics so far this year include the perennially interesting question of why our brains persist in keeping us fat, why women are great at math despite popular efforts to make us think otherwise, and how that magic elixir, coffee, acts on your brain to keep sleepiness at bay (at least for a little while).
So, what about you? What caught your eye this week?
Related articles
- Australia: Scientists discover first hybrid shark (sfgate.com)
- World’s First Hybrid Sharks Discovered (zazenlife.com)
- Hybrid sharks in the south Pacific (boingboing.net)
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