Word: fish
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Dates: during 2000-2009
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...study published in the July 30 edition of the scientific journal Public Library of Science, Natalia Ospina-Alvarez and Francesc Piferrer have gone a little further in explaining how that mechanism works. In laboratory tests, they have demonstrated that higher water temperatures result in more male fish...
...found that in fish that do have temperature-dependent sex determination [TSD], a rise in water temperature of just 1.5 degrees Celsius can change the male-to-female ratio from 1:1 to 3:1," says Piferrer, the study's co-author. In especially sensitive fish, a greater increase can throw the balance even more out of whack. Ospina-Alvarez and Piferrer have found that in the South American pejerrey, for example, an increase of 4 degrees Celsius can result in a population that is 98% male...
...Most research into fish sex determination has been done in the lab (for obvious reasons), but the pejerrey is one of the few species that scientists have been able to study in the field. And those studies have revealed that already, its proportion of males to females is skewed. "It could be because of chemical pollution or it could be because of climate change. We don't know," cautions Piferrer. "But the field data matches our predictions...
...this stage, it is hard to tell what these results bode for already declining fish populations around the world. Of the estimated 33,000 piscatorial species, only 5,000 have had their sex-determination mechanism affirmed. But the study by the two CSIC scientists also suggests that the percentage of TSD fish is lower than previously believed. In tests of 59 species believed to be reproductively sensitive to temperature, only 40 proved to be true TSDs...
...Arab woman investor has a long history. The Prophet Muhammad met his first wife, a wealthy Meccan trader, when she hired him to take caravans to Syria. When the Gulf's economy relied on pearls and fish, not gas and oil, absent men often left women in charge of their business affairs. Today, many Gulf women have lots of liquid assets, partly because of Muslim inheritance law. Shari'a dictates that a married woman's wealth is her own; spending on her household is her husband's responsibility...