Scientists Discover How Seahorses Have Sex

[matcom]

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They are among the most graceful and intriguing animals of the ocean and their strictly monogamous lifestyle breaks one of the golden rules of biology - it is the male rather than the female who is left holding the baby.

Scientists have unravelled another mystery of the seahorse and in the process discovered that these unusual fish may be more vulnerable to environmental pollution than was previously believed.

Until now it was thought the eggs and sperm of seahorses are protected against external pollutants because the creatures engage in a form of internal fertilisation, where the eggs and sperm come together inside a body cavity.

However, an anatomical study of the male has found that seahorses release sperm directly into seawater before these delicate "germ cells" of the body are brought quickly back into the protective environment of the male's incubation pouch.

Scientists believe that this key observation could explain why seahorses may be more vulnerable to environmental pollutants, such as heavy metals like mercury, than some marine biologists had thought possible.

http://news.independent.co.uk/world/science_technology/article2165477.ece