Hi stranger! Signing up for MypetMD is easy, free and puts the most relevant content at your fingertips.

Get Instant Access To

  • 24/7 alerts for pet-related recalls

  • Your own library of articles, blogs, and favorite pet names

  • Tools designed to keep your pets happy and healthy



or Connect with Facebook

By joining petMD, you agree to the Privacy Policy.


World-first Hybrid Shark Found Off Australia

By AFP News    January 04, 2012 at 12:02PM / (1) comments

SYDNEY - Scientists said on Tuesday that they had discovered the world's first hybrid sharks in Australian waters, a potential sign the predators were adapting to cope with climate change.

The mating of the local Australian black-tip shark with its global counterpart, the common black-tip, was an unprecedented discovery with implications for the entire shark world, said lead researcher Jess Morgan.

"It's very surprising because no one's ever seen shark hybrids before, this is not a common occurrence by any stretch of the imagination," Morgan, from the University of Queensland, told AFP.

"This is evolution in action."

Colin Simpfendorfer, a partner in Morgan's research from James Cook University, said initial studies suggested the hybrid species was relatively robust, with a number of generations discovered across 57 specimens.

The find was made during cataloguing work off Australia's east coast when Morgan said genetic testing showed certain sharks to be one species when physically they looked to be another.

The Australian black-tip is slightly smaller than its common cousin and can only live in tropical waters, but its hybrid offspring have been found 2,000 kilometers down the coast, in cooler seas.

It means the Australian black-tip could be adapting to ensure its survival as sea temperatures change because of global warming.

"If it hybridizes with the common species it can effectively shift its range further south into cooler waters, so the effect of this hybridizing is a range expansion," Morgan said.

"It's enabled a species restricted to the tropics to move into temperate waters."

Climate change and human fishing are some of the potential triggers being investigated by the team, with further genetic mapping also planned to examine whether it was an ancient process just discovered or a more recent phenomenon.

If the hybrid was found to be stronger than its parent species -- a literal survival of the fittest -- Simpfendorfer said it may eventually outlast its so-called pure-bred predecessors.

"We don't know whether that's the case here, but certainly we know that they are viable, they reproduce and that there are multiple generations of hybrids now that we can see from the genetic roadmap that we've generated from these animals," he said.

"Certainly it appears that they are fairly fit individuals."

The hybrids were extraorindarily abundant, accounting for up to 20 percent of black-tip populations in some areas, but Morgan said that didn't appear to be at the expense of their single-breed parents, adding to the mystery.

Simpfendorfer said the study, published late last month in Conservation Genetics, could challenge traditional ideas of how sharks had and were continuing to evolve.

"We thought we understood how species of sharks have separated, but what this is telling us is that in reality we probably don't fully understand the mechanisms that keep species of shark separate," he said.

"And in fact, this may be happening in more species than these two."

 

Image: Pascal Geraghty

Source: AFP

Comments  1

Leave Comment
  • Really ?
    01/04/2012 03:21pm

    when I first read the title of the article I was thinking Great White and Hammerhead, Mako and Hammerhead, Awesome shark + Awesome shark. Instead a black tip mates with a black tip. Not a big stretch of the imagination. NOW I want to see giant octopus and hammerhead. lets go.


  • Lifetime Credits:
  • Today's Credits:
Hurry Before All Seats are Taken!
Enroll
Be an A++ Pet Parent! Take fun & free courses to earn badges & certifications. Choose a course»

ARCHIVES

PETMD POLL

What do you use to prevent ticks from feeding on your pet?

 
MORE FROM PETMD.COM