- News Home
10 April 2014 11:44 am ,
Vol. 344 ,
Since 2002, researchers have reported that agricultural communities in the hot and humid Pacific Coast of Central...
Balkan endemic kidney disease surfaced in the 1950s and for decades defied attempts to finger the cause. It occurred...
The Pyrenean ibex, an impressive mountain goat that lived in the central Pyrenees in Spain, went extinct in 2000. But a...
Tight budgets are forcing NASA to consider turning off one or more planetary science projects that have completed their...
Ebola is not a stranger to West Africa—an outbreak in the 1990s killed chimpanzees and sickened one researcher. But the...
In an as-yet-unpublished report, an international panel of geoscientists has concluded that a pair of deadly...
Tropical disease experts tried and failed before to eradicate yaws, a rare disfiguring disease of poor countries. Now,...
- 10 April 2014 11:44 am , Vol. 344 , #6180
- About Us
ScienceShot: Fossils of Enigmatic Sea Creature Surface
17 January 2013 9:00 am
New fossil finds reveal that an enigmatic seafloor dweller first described more than a decade ago was armored and much larger than its modern-day kin. Cotyledion tylodes had a goblet-shaped body that surrounded a U-shaped gut (dark feature in fossil at left; arrows denote flow of food), and the animal spent its life anchored to the seafloor or to hard objects that had settled there, such as the molted exoskeletons of trilobites (artist's representation at right). C. tylodes was first described in 1999 based on a couple of fragmentary fossils unearthed from 520-million-year-old rocks in southern China. Previously, some scientists have proposed that the tentacled creatures were related to cnidarians, a group that contains jellyfish. But analyses of the new fossils—hundreds of well-preserved specimens extracted from the same ancient rocks—reveal that the animals belong to a group called entoprocts, aquatic creatures that attach to surfaces and filter their food from passing currents, the researchers report online today in Scientific Reports. The oldest undisputed fossils of entoprocts are less than one-third the age of C. tylodes, so the new fossils push back the origin of the entoproct lineage all the way back to the so-called Cambrian explosion, an interval when life diversified very quickly to produce most of the groups seen today or their ancestors. C. tylodes, which measured between 8 and 56 millimeters tall, dwarfed its modern kin, which typically range between 0.1 and 7 millimeters. Also unlike modern-day entoprocts, C. tylodes was covered with distinctive, scalelike features called sclerites—a hint, the scientists say, that such armor may have been more common among ancestral entoprocts than has been previously recognized.
See more ScienceShots.