Featured Research

from universities, journals, and other organizations

Earliest Evidence For Animal Life Discovered: Fossil Animal Steroids Date Back More Than 635 Million Years

Date:
February 5, 2009
Source:
University of California/Riverside
Summary:
Scientists have found the oldest evidence for animals in the fossil record. The researchers examined sedimentary rocks in south Oman, and found an anomalously high amount of steroids that date back to 635 million years ago, to around the end of the last ice age. The steroids are produced by sponges -- one of the simplest forms of multicellular animals.

Sponges are one of the simplest forms of multicellular animals.
Credit: Love lab, UC Riverside

An international research team of scientists from UC Riverside, the Massachusetts Institute of Technology and other institutions has found the oldest evidence for animals in the fossil record.

The researchers examined sedimentary rocks in south Oman, and found an anomalously high amount of steroids that date back to 635 million years ago, to around the end of the last ice age. The steroids are produced by sponges – one of the simplest forms of multicellular animals.

The researchers argue that the discovery of the sponges is evidence for multicellular animal life beginning 100 million years before the Cambrian explosion, a well-studied and unique episode in Earth history that began about 530 million years ago when, as indicated by the fossil record, animal life diversified rapidly.

The discovery can help scientists reconstruct Earth’s early ecosystems and explain how animal life may have first evolved on the planet.

“Our findings suggest that the evolution of multicellular animals began earlier than has been thought,” said Gordon Love, an assistant professor of Earth sciences, who led the research group. Love began working on the project while he was a postdoctoral researcher at MIT. “Moreover, sponges live on the seafloor, growing initially in shallow waters and spreading, over time, into deeper waters, implying the existence of oceanic environments which contained dissolved oxygen near the shallow seafloor around 635 million years ago.”

Study results appear in the Feb. 5 issue of Nature.

According to Love, the climatic shock of the extensive glacial episodes of the Neoproterozoic era (1000-542 million years ago) likely caused a major reorganization of marine ecosystems, perhaps by irrevocably altering ocean chemistry.

“This paved the way for the evolution of animal feeders living on the seafloor,” he said. “We believe we are converging on the correct date for the divergence of complex multicellular animal life, on the shallow ocean floor between 635 and 750 million years ago.”

The steroids that Love and his colleagues observed in the Omani rocks are essential biochemicals present in the cell membranes of the sponges, and help provide the membranes with structural support. The sponges are a few millimeters in size, immobile, and were filter feeders existing on the seafloor.

The sponge findings emerged from a project Love was working on at MIT (with Roger Summons, a professor of geobiology) in collaboration with Petroleum Development Oman. Using state-of–the-art techniques, he and his colleagues analyzed 64 Neoproterozoic-Cambrian sedimentary rock samples from the South Oman Salt Basin (SOSB), a region known for some of the best preserved rocks in the world. The researchers also established a robust stratigraphic and temporal framework for the SOSB rocks as part of their analysis.

Next, Love and his colleagues plan to screen other Neoproterozoic sedimentary rocks for animal steroids just before and through the Sturtian and Marinoan glaciations, the greatest ice ages known to have occurred on Earth during 850 to 635 million years ago.

“We aim to investigate the environmental context by which multicellular animal life became viable and flourished,” he said.

Love obtained his Ph.D. in chemistry from University of Strathclyde, Scotland. He was a recipient of the prestigious Natural Environment Research Council Postdoctoral Fellowship to carry out organic geochemical research at University of Newcastle, United Kingdom. He joined UCR’s Department of Earth Sciences in January 2007 after a postdoctoral appointment at the Massachusetts Institute of Technology.

Love has co-authored 50 research papers in international peer-reviewed scientific journals on petroleum geochemistry, geobiology, cosmochemistry, solid state nuclear magnetic resonance (NMR) spectroscopy and analytical chemistry.

Besides researchers at MIT, Love was joined in the study by colleagues at Geoscience Australia; the University of Newcastle upon Tyne, United Kingdom; the California Institute of Technology; and the University of Nottingham, United Kingdom.

The four-year study was funded by Petroleum Development Oman; the NASA Exobiology Program; the National Science Foundation Division of Earth Sciences; the Agouron Institute; and the NASA Astrobiology Institute.


Story Source:

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


Cite This Page:

University of California/Riverside. "Earliest Evidence For Animal Life Discovered: Fossil Animal Steroids Date Back More Than 635 Million Years." ScienceDaily. ScienceDaily, 5 February 2009. <www.sciencedaily.com/releases/2009/02/090204135731.htm>.
University of California/Riverside. (2009, February 5). Earliest Evidence For Animal Life Discovered: Fossil Animal Steroids Date Back More Than 635 Million Years. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2009/02/090204135731.htm
University of California/Riverside. "Earliest Evidence For Animal Life Discovered: Fossil Animal Steroids Date Back More Than 635 Million Years." ScienceDaily. www.sciencedaily.com/releases/2009/02/090204135731.htm (accessed September 16, 2014).

Share This



More Fossils & Ruins News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Museum Traces Fragments of Star-Spangled Banner

Museum Traces Fragments of Star-Spangled Banner

AP (Sep. 12, 2014) — As the Star-Spangled Banner celebrates its bicentennial, Smithsonian curators are still uncovering fragments of the original flag that inspired Francis Scott Key's poem. (Sept. 12) Video provided by AP
Powered by NewsLook.com
Spinosaurus Could Be First Semi-Aquatic Dinosaur

Spinosaurus Could Be First Semi-Aquatic Dinosaur

Newsy (Sep. 11, 2014) — New research has shown that the Spinosaurus, the largest carnivorous dinosaur, might have been just as well suited for life in the water as on land. Video provided by Newsy
Powered by NewsLook.com
Meet Spinosaurus, the First-Known Water Dinosaur

Meet Spinosaurus, the First-Known Water Dinosaur

AFP (Sep. 11, 2014) — Spinosaurus aegyptiacus was adapted for both land and water, and an exhibit featuring a life-sized model, based on new fossils unearthed in eastern Morocco, opens at the National Geographic Museum in Washington on Friday. Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
NatGeo Unveils Life-Size 'Spinosaurus'

NatGeo Unveils Life-Size 'Spinosaurus'

AP (Sep. 11, 2014) — Scientists announced new findings about the first ever non-bird dinosaur that could have lived much of its time in the water. National Geographic created a life-size 50-foot model of the prehistoric creature. (Sept. 11) 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