'Missing link' in shark evolution found in 380m-year-old Australian fossil

29. Mai 2015

Fossilised skeleton found in Kimberley shows sharks once had bone cells within cartilage, suggesting a sophisticated evolutionary path

A 380m-year-old fossil found in Western Australia has been hailed as the “missing link” in shark evolution, revealing the marine predator has a far more sophisticated lineage than previously thought.

The fossilised skeleton, jaws and teeth, found at the Gogo formation in the Kimberley region of WA, shows the ancient shark had a small amount of bone as well as cartilage.

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How sharks and rays claspers evolved

30. April 2015

How did animals like sharks and skates evolve claspers—paired penislike organs found on male pelvic fins—like the ones seen on the male skate on the left? For years, their origin has remained an evolutionary mystery, but now, a new study suggests that regulation of the genetic circuit known as the Sonic hedgehog (Shh) pathway by sex hormones may be the answer.

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Trade in Shark Fins Takes a Plunge

26. Februar 2015

An analysis of trade statistics suggests that efforts to educate shark fin soup consumers is working

In 2013, the environmental group WildAid reported that demand for shark fin soup in China had dropped by 50 to 70 percent, offering some hope for the estimated 25% of species of sharks and their relatives, that are threatened with extinction. Many experts thought those numbers sounded too good to be true.

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