Featured Research

from universities, journals, and other organizations

Most vertebrates -- including humans -- descended from ancestor with sixth sense

Date:
October 11, 2011
Source:
Cornell University
Summary:
A new study that caps more than 25 years of work finds that the vast majority of vertebrates -- some 30,000 species of land animals (including humans) and a roughly equal number of ray-finned fishes -- descended from a common ancestor that had a well-developed electroreceptive system.

People experience the world through five senses but sharks, paddlefishes and certain other aquatic vertebrates have a sixth sense: They can detect weak electrical fields in the water and use this information to detect prey, communicate and orient themselves.
Credit: Mika Specta / Fotolia

People experience the world through five senses but sharks, paddlefishes and certain other aquatic vertebrates have a sixth sense: They can detect weak electrical fields in the water and use this information to detect prey, communicate and orient themselves.

A study in the Oct. 11 issue of Nature Communications that caps more than 25 years of work finds that the vast majority of vertebrates -- some 30,000 species of land animals (including humans) and a roughly equal number of ray-finned fishes -- descended from a common ancestor that had a well-developed electroreceptive system.

This ancestor was probably a predatory marine fish with good eyesight, jaws and teeth and a lateral line system for detecting water movements, visible as a stripe along the flank of most fishes. It lived around 500 million years ago. The vast majority of the approximately 65,000 living vertebrate species are its descendants.

"This study caps questions in developmental and evolutionary biology, popularly called 'evo-devo,' that I've been interested in for 35 years," said Willy Bemis, Cornell professor of ecology and evolutionary biology and a senior author of the paper. Melinda Modrell, a neuroscientist at the University of Cambridge who did the molecular analysis, is the paper's lead author.

Hundreds of millions of years ago, there was a major split in the evolutionary tree of vertebrates. One lineage led to the ray-finned fishes, or actinopterygians, and the other to lobe-finned fishes, or sarcopterygians; the latter gave rise to land vertebrates, Bemis explained. Some land vertebrates, including such salamanders as the Mexican axolotl, have electroreception and, until now, offered the best-studied model for early development of this sensory system. As part of changes related to terrestrial life, the lineage leading to reptiles, birds and mammals lost electrosense as well as the lateral line.

Some ray-finned fishes -- including paddlefishes and sturgeons -- retained these receptors in the skin of their heads. With as many as 70,000 electroreceptors in its paddle-shaped snout and skin of the head, the North American paddlefish has the most extensive electrosensory array of any living animal, Bemis said.

Until now, it was unclear whether these organs in different groups were evolutionarily and developmentally the same.

Using the Mexican axolotl as a model to represent the evolutionary lineage leading to land animals, and paddlefish as a model for the branch leading to ray-finned fishes, the researchers found that electrosensors develop in precisely the same pattern from the same embryonic tissue in the developing skin, confirming that this is an ancient sensory system.

The researchers also found that the electrosensory organs develop immediately adjacent to the lateral line, providing compelling evidence "that these two sensory systems share a common evolutionary heritage," said Bemis.

Researchers can now build a picture of what the common ancestor of these two lineages looked like and better link the sensory worlds of living and fossil animals, Bemis said.

Co-authors include Glenn Northcutt, a world expert on vertebrate neuroanatomy based at the Scripps Institution of Oceanography; and Claire Baker at the University of Cambridge, whose lab contributed molecular analyses.

The study was funded by the Biotechnology and Biological Sciences Research Council in the United Kingdom, National Institutes of Health, National Science Foundation, Whitehall Foundation and Tontogany Creek Fund.


Story Source:

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


Journal Reference:

  1. Melinda S. Modrell, William E. Bemis, R. Glenn Northcutt, Marcus C. Davis, Clare V.H. Baker. Electrosensory ampullary organs are derived from lateral line placodes in bony fishes. Nature Communications, 2011; 2: 496 DOI: 10.1038/ncomms1502

Cite This Page:

Cornell University. "Most vertebrates -- including humans -- descended from ancestor with sixth sense." ScienceDaily. ScienceDaily, 11 October 2011. <www.sciencedaily.com/releases/2011/10/111011163057.htm>.
Cornell University. (2011, October 11). Most vertebrates -- including humans -- descended from ancestor with sixth sense. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2011/10/111011163057.htm
Cornell University. "Most vertebrates -- including humans -- descended from ancestor with sixth sense." ScienceDaily. www.sciencedaily.com/releases/2011/10/111011163057.htm (accessed July 31, 2014).

Share This




More Plants & Animals News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Visitors Feel Part of the Pack at Wolf Preserve

Visitors Feel Part of the Pack at Wolf Preserve

AP (July 31, 2014) Seacrest Wolf Preserve on the northern Florida panhandle allows more than 10,000 visitors each year to get up close and personal with Arctic and British Columbian Wolves. (July 31) Video provided by AP
Powered by NewsLook.com
Florida Panther Rebound Upsets Ranchers

Florida Panther Rebound Upsets Ranchers

AP (July 31, 2014) With Florida's panther population rebounding, some ranchers complain the protected predators are once again killing their calves. (July 31) Video provided by AP
Powered by NewsLook.com
Dangerous Bacteria Kills One in Florida

Dangerous Bacteria Kills One in Florida

AP (July 31, 2014) Sarasota County, Florida health officials have issued a warning against eating raw oysters and exposing open wounds to coastal and inland waters after a dangerous bacteria killed one person and made another sick. (July 31) Video provided by AP
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
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:
from the past week

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