Featured Research

from universities, journals, and other organizations

It's all in the way we move: Bone form and locomotor behavior in bipedal and quadrupedal marsupials

Date:
March 13, 2013
Source:
University of the Witwatersrand
Summary:
A new study examined the connections between bone form and locomotor behavior in bipedal and quadrupedal marsupials.

Australian red kangaroo.
Credit: Dale Mitchell / Fotolia

When, how and why modern humans first stood up and walked on two legs is considered to be one of the greatest missing links in our evolutionary history. Scientists have gone to the far ends of the Earth -- and the wonderful creatures in it -- to look for answers to why we walk the way we walk.

In the latest such search, researchers from the University of the Witwatersrand in Johannesburg (South Africa) have taken a closer look at bipedal kangaroos and wallabies and how they move compared to their cousin-marsupials, such as the quadrupedal Tasmanian wolf.

In an article published online in the scientific journal PLoS ONE on 12 March 2013, the researchers examine connections between bone form and locomotor behaviour in bipedal and quadrupedal marsupials. Read the article here

The study was led by Dr Kristian Carlson, Senior Researcher at the Institute for Human Evolution (IHE) at Wits University. Contributing authors include: Dr Tea Jashashvili, Postdoctoral Fellow at the IHE at Wits University; Kimberley Houghton, MSc candidate at the IHE at Wits University; Dr Michael Westaway from the Queensland Museum (Australia); and Dr Biren Patel from the University of Southern California (US).

Their article is entitled Joint loads in marsupial ankles reflect habitual bipedalism versus quadrupedalism. The research demonstrates that bipedal marsupials, such as kangaroos and wallabies, experience greater forces through their hind limb joints (e.g., ankles) when walking, compared to other marsupials that walk on four legs.

The study has several important implications in the area of research known as functional morphology.

Characterising forces that joints experience during movement is imperative to understanding how the joints of animals function and facilitate such movements. Documenting these forces, however, is extremely difficult for practical reasons.

Using physical instruments to measure joint forces is impossible without altering the natural movements of animals. By combining computed tomography (CT) and image analyses, the team of researchers was able to estimate joint forces in a non-invasive, accurate manner.

As the group predicted at the outset of the study, marsupials supporting their body with only two hind limbs during movement sustain higher estimated forces in their joints compared to marsupials that support their body with all four limbs during movement. This finding offers insight into the structural uniqueness of hind limb joints (e.g., ankles) of bipedal marsupials.

Members of the team are currently expanding the published study into the next phase of a larger project by documenting the same phenomenon in primates in order to investigate whether bipedal humans differ from related quadrupedal primates in parallel (or different) ways as bipedal marsupials differ from related quadrupedal marsupials.

By comparing analogous systems in primates and marsupials, team members will garner potentially new insights into the mechanics of human bipedalism. Such insights will advance current understanding of the morphological adaptations expressed by our distant hominin ancestors (e.g., australopithecines).

These insights will prove particularly timely considering the emerging trend in recognizing substantial variation in the form of bipedalism expressed by our hominin ancestor.


Story Source:

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


Journal Reference:

  1. Kristian J. Carlson, Tea Jashashvili, Kimberley Houghton, Michael C. Westaway, Biren A. Patel. Joint Loads in Marsupial Ankles Reflect Habitual Bipedalism versus Quadrupedalism. PLoS ONE, 2013; 8 (3): e58811 DOI: 10.1371/journal.pone.0058811

Cite This Page:

University of the Witwatersrand. "It's all in the way we move: Bone form and locomotor behavior in bipedal and quadrupedal marsupials." ScienceDaily. ScienceDaily, 13 March 2013. <www.sciencedaily.com/releases/2013/03/130313112422.htm>.
University of the Witwatersrand. (2013, March 13). It's all in the way we move: Bone form and locomotor behavior in bipedal and quadrupedal marsupials. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2013/03/130313112422.htm
University of the Witwatersrand. "It's all in the way we move: Bone form and locomotor behavior in bipedal and quadrupedal marsupials." ScienceDaily. www.sciencedaily.com/releases/2013/03/130313112422.htm (accessed April 18, 2014).

Share This



More Plants & Animals News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Vermont Goat Meat Gives Refugees Taste of Home

Vermont Goat Meat Gives Refugees Taste of Home

AP (Apr. 18, 2014) Dairy farmers and ethnic groups in Vermont are both benefiting from a unique collaborative effort that's feeding a growing need for fresh and affordable goat meat. (April 18) Video provided by AP
Powered by NewsLook.com
First Ever 'Female Penis' Discovered In Animal Kingdom

First Ever 'Female Penis' Discovered In Animal Kingdom

Newsy (Apr. 18, 2014) Not only are these newly discovered bugs' sex organs reversed, but they also mate for up to 70 hours. Video provided by Newsy
Powered by NewsLook.com
The Great British Farmland Boom

The Great British Farmland Boom

Reuters - Business Video Online (Apr. 17, 2014) Britain's troubled Co-operative Group is preparing to cash in on nearly 18,000 acres of farmland in one of the biggest UK land sales in decades. As Ivor Bennett reports, the market timing couldn't be better, with farmland prices soaring over 270 percent in the last 10 years. Video provided by Reuters
Powered by NewsLook.com
Flamingo Frenzy Ahead of Zoo Construction

Flamingo Frenzy Ahead of Zoo Construction

AP (Apr. 17, 2014) With plenty of honking, flapping, and fluttering, more than three dozen Caribbean flamingos at Zoo Miami were rounded up today as the iconic exhibit was closed for renovations. (April 17) 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