Featured Research

from universities, journals, and other organizations

Penis worms show the evolution of the digestive system

Date:
October 26, 2012
Source:
Uni Research
Summary:
Scientists have revealed that the enigmatic marine penis worms (priapulids) develop their intestine as humans, fish or starfish do. This surprising finding shows that very different animals share a common way of forming a gut.

Adult Priapulus caudatus.
Credit: Bruno Vellutini, Sars International Centre for Marine Molecular Biology

A team of scientists has revealed that the enigmatic marine penis worms (priapulids) develop their intestine as humans, fish or starfish. This surprising finding shows that very different animals share a common way of forming a gut.

A research team led by Dr. Andreas Hejnol from the Sars International Centre for Marine Molecular Biology in Norway, examined the formation of the gut and the expression of genes needed to form the mouth and the anus in priapulid embryos. Priapulids are an obscure group of marine worms that live in shallow waters.

"Surprisingly, priapulids form the gut like humans, fish, frogs, starfish and sea urchins -and all of them even use the same genes. It does not mean that these penis worms are now closely related to humans. Instead the fact that different animals share a common way of forming the gut suggests that the embryological origins of the human intestine and how it develops are much older than previously thought -- most likely over 500 million years, when the first bilaterally symmetric animals appeared on Earth" remarks Hejnol.

The study, featured online on the 25th of October in the journal Current Biology, represents the first description of the entire embryonic development of these enigmatic animals.

"Priapulids are important for understanding the evolution of animals, because they are thought to be among the first bilaterally symmetric animals and have changed very little since the Earth's Cambrian Period" says first author Dr José M. Martín-Durán.

Bilaterally symmetric animals (99% of all animals) are those with a left and right body side. Historically, they have been divided into two large groups based on major differences in how the gut develops in the embryo. The intestine is an essential organ, and that is why it is present in nearly all animal species. The gut develops very early, when some cells move towards the inside of the embryo, usually at a defined region that is called the 'blastopore'.

"The important point is that in some animals this region becomes the mouth, while in others it becomes the anus. For more than a century, this difference has captivated scientists, but there is not a completely satisfactory explanation for it yet" explains Hejnol.

The work shows how important it is to study the vast diversity of animals found in the oceans.

"Priapulids still hide a lot of secrets to unravel, which will have a great influence on our understanding of the origin of other major organs, such as the brain, blood or legs" concludes Hejnol.

They reproduce in winter time, so the scientists have to travel regularly to the west coast of Sweden during the ice-cold season to get a hold of them.

"We sail the fjords dredging in areas where they are abundant, collecting animals and later getting embryos from them in the lab. Although thrilling, sometimes the collection trips turn into real adventures, with low temperatures, snow or even frozen waters" says Martín-Durán.


Story Source:

The above story is based on materials provided by Uni Research. Note: Materials may be edited for content and length.


Journal Reference:

  1. José M. Martín-Durán, Ralf Janssen, Sofia Wennberg, Graham E. Budd, Andreas Hejnol. Deuterostomic Development in the Protostome Priapulus caudatus. Current Biology, 2012; DOI: 10.1016/j.cub.2012.09.037

Cite This Page:

Uni Research. "Penis worms show the evolution of the digestive system." ScienceDaily. ScienceDaily, 26 October 2012. <www.sciencedaily.com/releases/2012/10/121026084350.htm>.
Uni Research. (2012, October 26). Penis worms show the evolution of the digestive system. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2012/10/121026084350.htm
Uni Research. "Penis worms show the evolution of the digestive system." ScienceDaily. www.sciencedaily.com/releases/2012/10/121026084350.htm (accessed September 30, 2014).

Share This



More Plants & Animals News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) — A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
Dolphins Might Use Earth's Magnetic Field As A GPS

Dolphins Might Use Earth's Magnetic Field As A GPS

Newsy (Sep. 30, 2014) — A study released Monday suggests dolphins might be able to sense the Earth's magnetic field and possibly use it as a means of navigation. Video provided by Newsy
Powered by NewsLook.com
How To Battle Stink Bug Season

How To Battle Stink Bug Season

Newsy (Sep. 30, 2014) — Homeowners in 33 states grapple with stink bugs moving indoors at this time of year. Here are a few tips to avoid stink bug infestations. Video provided by Newsy
Powered by NewsLook.com
California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) — Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins