With flowers in bursts of orange and red, flame azaleas attract several types of pollinators. But these azaleas must rely almost entirely on butterflies to reproduce, researchers have found.

The anther and the stigma — the male and female parts of the flower where pollen is produced and then germinated — are too far apart for other insects to be effective. The azalea relies primarily on eastern tiger swallowtails.

The findings, which appear in the American Naturalist, suggest that some plants depend on very few insect species for pollination.

Fish may flee warming equator

As the climate warms, fish may flee the equator for cooler waters with more oxygen, said a study in the journal Science.

"The oceans are warming up, and the amount of oxygen in the ocean is going down and will continue to go down," said Curtis Deutsch, an oceanographer at the University of Washington and one of the study's authors. "When you put those two things together, it will limit the habitat space an animal has."

Their study predicts that viable habitats will shift away from the equator, altering 14 to 26 percent of the current ranges of the fish. A second study suggests that coral will similarly be displaced.

Sawfish resort to 'virgin births'

In a study in the journal Current Biology, Stony Brook University researchers working with Florida scientists discovered seven endangered sawfish living in two rivers conceived through a process called parthenogenesis — the production of offspring without sex or male sperm, or in simpler terms, "virgin birth."

Scientists have known that insects, crabs and other invertebrates can reproduce without partners. Female birds, reptiles and sharks in captivity have also occasionally surprised scientists with virgin births. But until now, researchers never knew whether the behavior happened in the wild, said Andrew Fields, a Stonybook doctoral student.

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