Limb cells turned into genitals in lab

5 November 2014 Last updated at 18:02

By Melissa HogenboomScience reporter, BBC News

Lizard males have paired genitals called hemipenes - now research shows their genetic origin comes from limbs

In order for vertebrates to evolve from the sea to the land, some drastic evolutionary changes were needed.

Their ancient sea-dwelling ancestors had no need for external sex organs whereas their land relatives did.

Now a new study offers insights into the genetic changes that allowed land-dwelling animals to develop sex organs.

The Nature research suggests the key to the origin of genitalia lies in the limbs, at least in snakes and lizards.

For their genitals - called hemipenes - to develop, a signalling centre instructs the relevant genes to switch on.

Initially the researchers wanted to understand why snakes do not develop limbs but then soon discovered that the earliest stages of genital development closely resembled limb formation.

They found that when a given nudge, embryonic limb cells of lizards and snakes could then be turned into genitals. In mice, tail bud cells could be manipulated in a similar way.

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Hawkmoths Use Ultrasound to Combat Bats

July 4, 2013 — For years, pilots flying into combat have jammed enemy radar to get the drop on their opponents. It turns out that moths can do it, too.

A new study co-authored by a University of Florida researcher shows hawkmoths use sonic pulses from their genitals to respond to bats producing the high-frequency sounds, possibly as a self-defense mechanism to jam the echolocation ability of their predators.

Echolocation research may be used to better understand or improve ultrasound as a vital tool in medicine, used for observing prenatal development, measuring blood flow and diagnosing tumors, among other things. The study appears online today in the journal Biology Letters.

Study co-author Akito Kawahara, assistant curator of Lepidoptera at the Florida Museum of Natural History on the UF campus, said ultrasound has only been demonstrated in one other moth group.

"This is just the first step toward understanding a really interesting system," Kawahara said. "Echolocation research has been focused on porpoises, whales and dolphins. We know some insects produce the sounds, but this discovery in an unrelated animal making ultrasound, potentially to jam the echolocation of bats, is exciting."

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