A female <i>C. maculatus</i>seed beetle (above right) mating with a male (left) tries to free herself by kicking him with her hind legs.<br> <br> It's not easy: Male beetles have long and spiny genitalia that may act as anchors.<br> <br> "Males can position their genitalia in an optimal way inside the female as the male releases sperm," said study co-author Göran Arnqvist, an evolutionary biologist at Sweden's Uppsala University.<br> <br> In a study to be published in March, Arnqvist and colleagues found that individuals with the longest spines are more successful in reproducing than their less endowed rivals.<br> <br> The new research offers the first proof that having huge spines that injure females affords males a reproductive advantage.
A female C. maculatusseed beetle (above right) mating with a male (left) tries to free herself by kicking him with her hind legs.

It's not easy: Male beetles have long and spiny genitalia that may act as anchors.

"Males can position their genitalia in an optimal way inside the female as the male releases sperm," said study co-author Göran Arnqvist, an evolutionary biologist at Sweden's Uppsala University.

In a study to be published in March, Arnqvist and colleagues found that individuals with the longest spines are more successful in reproducing than their less endowed rivals.

The new research offers the first proof that having huge spines that injure females affords males a reproductive advantage.
Photograph courtesy of Fleur Champion de Crespigny

''Torture'' Phalluses Give Beetles Breeding Boost

Males across seed beetle species have wildly divergent sexual parts that feature spikes, hooks, and barbs. A new study finds that the longest and spiniest beetle organs are most successful in reproducing.

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