Navigation Links
Shell-breaking crabs lived 20 million years earlier than thought
Date:4/22/2008

While waiting for colleagues at a small natural history museum in the state of Chiapas, Mexico last year, Cornell paleontologist Greg Dietl chanced upon a discovery that has helped rewrite the evolutionary history of crabs and the shelled mollusks upon which they preyed.

In a museum display case he recognized a 67- to 69-million-year-old fossil from the Late Cretaceous period of a big crab with an oversized right claw. Such crabs with claws of different sizes were not known to exist until the early Cenozoic era, about 20 million years later. Aside from being larger than most known Late Cretaceous crabs (about the size of today's Florida stone crabs) and having asymmetrical claws, this ancient crab also sported a curved tooth on the movable finger of the larger right claw. This was another specialized adaptation that paleontologists thought developed millions of years later for peeling snail shells open.

"I immediately had to point it out to my colleagues around me," said Dietl, an adjunct professor in Cornell's Department of Earth and Atmospheric Sciences and director of collections at the Cornell-affiliated Paleontological Research Institution in Ithaca. "I was really excited when I found it. The fossil re-opens the question of the role crabs played in the well-documented restructuring of marine communities that occurred during the Mesozoic era [251 million years ago to 65 million years ago]."

The discovery led to a study, published March 10 in the online version of the Royal Society's Biology Letters journal, coauthored by Francisco J. Vega, a geologist at the Universidad Nacional Autnoma de Mxico.

The museum's staff showed Dietl and colleagues another fossil of the same species in a back room. Both specimens, found near the town of Ocozocoautla in southeastern Mexico, are the oldest fossils with these unique features on record and represent a new species, Megaxantho zogue.

The large right "crusher" claw generated a great deal of force to break shells, while the smaller left cutter claw moved faster and could manipulate prey into position. Also, the curved tooth increased the power of the claw.

Dietl hopes the discovery will spur other researchers to search for similar examples of these curved tooth structures from the Late Cretaceous period, just prior to the extinction of the dinosaurs.

Although Megaxantho crabs became extinct around 65 million years ago, these features evolved again in other crab species throughout the Cenozoic era, leading to present-day crabs, according to the study. The repeated evolution suggests that such power-enhancing adaptations may evolve during times and places where resources are abundant and accessible, Dietl said.

The study may be relevant to the current stresses of habitat loss, overfishing, climate change and other human-influenced activities that are reducing the productive capacity of the environment.

"We may be diminishing the capacity of organisms to adapt in novel ways," a consideration that conservationists may need to account for in future strategies for protecting natural areas, he said.


'/>"/>

Contact: Blaine Friedlander
bpf2@cornell.edu
607-254-8093
Cornell University Communications
Source:Eurekalert

Related biology news :

1. Scientists discover 356 animal inclusions trapped in 100 million years old opaque amber
2. NIH awards $6.5 million grant to UT Southwestern to develop new antibiotic
3. A fossilized giant rhino bone questions the isolation of Anatolia, 25 million years ago
4. University of Colorado at Boulder awarded $1 million for biofuels research
5. Carnegie Mellon receives $1.85 million
6. Missouri board grants Washington University Sustainability Center $3 million
7. UA-led research team awarded $50 million to solve plant biologys grand challenge questions
8. Helios Education Foundation invests $6.5 million
9. Nanomedicine research for prostate cancer supported by $5 million gift
10. NOAA invests $3 million for unmanned aircraft system testing
11. $13 million federal grant for research into vascular disease awarded to Weill Cornell
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/13/2017)... , Feb. 13, 2017  RSA Conference -- RSA, ... that is designed to enhance fraud detection and ... in the RSA Fraud & Risk Intelligence Suite. ... to leverage additional insights from internal and external ... better protect their customers from targeted cybercrime attacks. ...
(Date:2/10/2017)... -- Research and Markets has announced the ... Scientific and Commercial Aspects" to their offering. ... Biomarkers play ... therapy for selection of treatment as well for monitoring the ... disease in modern medicine. Biochip/microarray technologies and next generation sequencing ...
(Date:2/8/2017)... YORK , Feb. 8, 2017 About ... individual,s voice to match it against a stored ... such as pitch, cadence, and tone are compared ... require minimal hardware installation, as most PCs already ... for different transactions. Voice recognition biometrics are most ...
Breaking Biology News(10 mins):
(Date:3/22/2017)... ... March 21, 2017 , ... Okyanos Cell Therapy has ... part of their live events series, “Stem Cell Therapy: The Next Phase in the ... the 2013 Stem Cell Research and Therapy Act, Okyanos maintains a mission ...
(Date:3/22/2017)... ... , ... The Conference Forum has announced the launch of the 5th Annual ... 2017, at the Colonnade Hotel in Boston, MA. The CMO Summit is the only ... and support. , “The Chief Medical Officer faces a unique set of challenges at ...
(Date:3/22/2017)... ... March 22, 2017 , ... March 22, 2017...Council for ... another green revolution, one that utilizes technological innovation in smart, sustainable ways. Humans depend ... life such as aesthetics and environmental stability. This paper is the first in a ...
(Date:3/22/2017)... FRANCISCO , March 22, 2017   ... fastest growing genetic information companies, today announced the ... diagnosis of Spinal Muscular Atrophy (SMA) , ... leading lethal genetic disorders among infants as well ... in childhood. The new test, announced during the ...
Breaking Biology Technology: