Simplest known animals engage in sex

Oct 10, 2005

A Yale University study suggests even the most simple of animals engage in sex. Ana Signorovitch and colleagues have demonstrated placozoans, the simplest known free-living animals, undergo a sexual phase in their life cycle.

Placozoans possess the smallest genome of any known animal and are composed of only four different cell types. While asexual reproduction has been observed in placozoans, no evidence of sexual reproduction has been documented. The biology of the organisms remains largely unknown.

Signorovitch and colleagues utilized molecular genetics to investigate if placozoans reproduce sexually. Because asexual and sexual animals have distinct patterns of gene variation, the researchers studied the DNA sequences of several genes from a sample placozoan population of 10 individuals.

Genetic signatures consistent with a sexual mode of reproduction were observed. Within-individual and overall DNA diversity were found to be consistent with levels seen in sexually reproducing organisms. Also, genetic recombination and sharing of gene variants were observed, supporting the presence of a sexual phase in the placozoan life cycle.

Signorovitch said the findings indicate placozoans have or had the ability to reproduce sexually.

The research appears in the online early edition of the Proceedings of the National Academy of Sciences.

Copyright 2005 by United Press International

Explore further: A two generation lens: Current state policies fail to support families with young children

add to favorites email to friend print save as pdf

Related Stories

Controlling the transition between generations

18 minutes ago

Rafal Ciosk and his group at the FMI have identified an important regulator of the transition from germ cell to embryonic cell. LIN-41 prevents the premature onset of embryonic transcription in oocytes poised ...

News Corp opposes Google in EU antitrust case

18 minutes ago

The media conglomerate controlled by Rupert Murdoch is joining the fray in Google's protracted European antitrust case, saying the technology company unfairly distorts competition.

Recommended for you

New hadrosaur noses into spotlight

Sep 19, 2014

Call it the Jimmy Durante of dinosaurs – a newly discovered hadrosaur with a truly distinctive nasal profile. The new dinosaur, named Rhinorex condrupus by paleontologists from North Carolina State Univer ...

Scholar tracks the changing world of gay sexuality

Sep 19, 2014

With same-sex marriage now legalized in 19 states and laws making it impossible to ban homosexuals from serving in the military, gay, lesbian and bisexual people are now enjoying more freedoms and rights than ever before.

User comments : 0