. 24/7 Space News .
EARLY EARTH
Tiny fossil horses put their back into it
by Staff Writers
Boston MA (SPX) Apr 29, 2016


File image.

Modern horses are expert runners. They reach top speeds using a special running gait in which they hold their back stiff as they move. A new study reveals that tiny fossil ancestors of modern horses may have moved quite differently to their living counterparts.

"Horses provide a perfect case-study on the evolution of running because they have such an amazing fossil record", explains author Dr. Katrina Jones, a post-doctoral researcher in Harvard's Museum of Comparative Zoology.

Dating back over 50 million years, the oldest horse ancestors were no bigger than a house cat. From those ancient horse ancestors, some lineages evolved larger sizes, grazing habit and limbs that were specialized for running. This new study suggests that the stiff-backed gait of modern horses likely evolved to save energy while running as horses got bigger through their evolution.

"For over a century, researchers studied the feet of fossil horses to explain how they evolved features specialized for running," explains Jones, "but very little is known about how the backbone might be involved in this famous transition."

Four-legged mammals tend to move their lower back during running to help increase speed and regulate breathing. But horses are unusual because they restrict the motion of their lumbar spine to a single joint near their rump. Jones wanted to find out if this unusual pattern was shared by extinct horses, and how increasing size in horse evolution may have affected their back mobility and running style.

To understand the evolution of the back in fossil horses, Jones first examined the anatomy and mobility of the spine in modern domestic horses. The shape of the vertebral joints - bony connections between the vertebrae - help determine how much motion occurs at each joint. Armed with this information, Jones then measured the shape of vertebral joints in 16 species of fossil horses spanning their full size and age range.

She found that small fossil horses, such as Hyracotherium (the 'dawn horse'), had quite different anatomy of the vertebral joints than their modern equivalents. This anatomy suggests more mobility was possible in the middle and lower portions of their back. Anatomy of these joints was also linked to body size - evolutionary branches which evolved greater size tended to display more restrictive joints.

Jones hypothesizes that stability of the backbone evolved as a response to the mechanical challenge of large size in horses. Says Jones,"the energy required for a large animal to move at high speed can be extreme, so increasing running efficiency by minimizing motions of the trunk makes sense."

Jones speculates that these tiny ancient horses may not have been running in the same way as modern horses. Some living mammals can switch between stiff-backed and flex-backed running as they increase in speed.

This could be one potential model for the evolution of specialized stiff-backed running in horses. This study reveals a new insight into a famous case-study of locomotor adaptation.

Jones explains: "the findings are significant because they show how the backbone - a relatively understudied part of the anatomy - can provide new perspectives on locomotor transitions."


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


.


Related Links
Harvard University
Explore The Early Earth at TerraDaily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
EARLY EARTH
Mammal-like reptile survived much longer than thought
Kyoto, Japan (SPX) Apr 28, 2016
Teeth can reveal a lot, such as how the earliest mammals lived with their neighbors. Researchers have uncovered dozens of fossilized teeth in Kuwajima, Japan and identified this as a new species of tritylodontid, an animal family that links the evolution of mammals from reptiles. This finding suggests that tritylodontids co-existed with some of the earliest mammal species for millions of years, ... read more


EARLY EARTH
First rocket made ready for launch at Vostochny spaceport

Supernova iron found on the moon

Russia to shift all Lunar launches to Vostochny Cosmodrome

Lunar lava tubes could help pave way for human colony

EARLY EARTH
NASA seeks industry ideas for an advanced Mars satellite

Rover mini-walkabout to find clay mineral continues

Russia, Italy plan first bid to explore beneath mars surface in 2018

First light for ExoMars

EARLY EARTH
When technology bites back

Menstruation in spaceflight: Options for astronauts

Tech industry titans urge US to better fund science ed

Space Subcommittee examines commercial challenges

EARLY EARTH
China to become aerospace power by 2030

150 Long March rocket launches scheduled 2016-2020

China aims for deeper space with new generation rockets

China targets 2020 Mars mission launch: official

EARLY EARTH
15 years of Europe on the International Space Station

US-Russia Space Projects Set Example of Good Cooperation

Russia, US discuss boosting efficiency of cooperation at ISS

BEAM successfully installed to the International Space Station

EARLY EARTH
Soyuz meets its multi-satellite payload for Friday's Arianespace launch

Europe makes fourth attempt to launch Russian rocket

Sentinel-1B in position for liftoff

Arianespace cooperation with Russia remains smooth amid sanctions

EARLY EARTH
Kepler spacecraft recovered and returned to the K2 Mission

Lone planetary-mass object found in family of stars

University of Massachusetts Lowell PICTURE-B Mission Completed

Stars strip away atmospheres of nearby super-Earths

EARLY EARTH
Liquid spiral vortex discovered

New material combines useful, typically incompatible properties

Researchers coax molecules into assembling themselves

Antimatter helps to unveil the secrets of liquid crystals









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.