Navigation Links
Walking tall to protect the species
Date:12/12/2007

The transition from apes to humans may have been partially triggered by the need to stand on two legs, in order to safely carry heavier babies. This theory1 of species evolution presented by Lia Amaral from the University of So Paulo in Brazil has just been published online in Springers journal, Naturwissenschaften.

For safety, all nonhuman primates carry their young clinging to their fur from birth, and species survival depends on it. The carrying pattern changes as the infant grows. Newborns are carried clinging to their mothers stomach, often with additional support. Months later, infants are carried over the adult body usually on the mothers back, and this carrying pattern lasts for years in apes. However, this necessity to carry infants safely imposes limits on the weight of the infants.

Through a detailed mechanical analysis of how different types of apes - gibbons, orangutans and gorillas - carry their young, looking at the properties of ape hair, infant grip, adult hair density and carrying position, Amaral demonstrates a relationship between infant weight, hair friction and body angle which ensures ape infants are carried safely.

Amaral also shows how the usual pattern of primate carrying of heavy infants is incompatible with bipedalism. African apes have to persist with knuckle-walking on all fours, or quadruped position, in order to stop their young from slipping off their backs.

The author goes on to suggest that the fall in body hair in primates could have brought on bipedality as a necessary consequence, through the strong selective pressure of safe infant carrying, as infants were no longer able to cling to their mothers body hairs. In the authors opinion, safe carrying of heavy infants justified the emergence of the biped form of movement. Although an adult gorilla is much heavier than an adult human, its offspring is only half the weight of a human baby.

Amaral concludes that this evolution to bipedality has important consequences for the female of the species. Indeed, it frees the arms and hands of males and juveniles, but females have their arms and hands occupied with their young. This restriction of movement placed limits on food gathering for biped females carrying their infants, and may have been at the origin of group cooperation.


'/>"/>

Contact: Joan Robinson
joan.robinson@springer.com
49-622-148-78130
Springer
Source:Eurekalert

Related biology news :

1. Rain forest protection works in Peru
2. Same gene protects from 1 disease, opens door to another
3. Conservation International and Toyota partner to protect Philippines rain forests
4. Fungus genome yielding answers to protect grains, people and animals
5. Genes that both extend life and protect against cancer identified
6. Intravenous gene therapy protects normal tissue of mice during whole-body radiation
7. Rosemary chicken protects your brain from free radicals
8. Genes identified to protect brassicas from damaging disease
9. Antioxidants could provide all-purpose radiation protection
10. Secure Services Corp. Achieves Milestone in United States Identity Protection with the Launch of the SSC SHAPE Card Management Solution
11. Omega-3 fatty acids protect against Parkinsons, study says
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/24/2017)... DUBLIN , Mar 24, 2017 Research ... Vehicle Access System Market Analysis & Trends - Industry Forecast to ... ... poised to grow at a CAGR of around 15.1% over the ... This industry report analyzes the market estimates and forecasts for ...
(Date:3/22/2017)... , March 21, 2017 Vigilant Solutions ... serving law enforcement agencies, announced today the appointment of ... director of public safety business development. Mr. ... enforcement experience, including a focus on the aviation transportation ... most recent position, Mr. Sheridan served as the Aviation ...
(Date:3/9/2017)... , March 9, 2017 4Dx has publicly ... Lung Imaging Workshop at the University of Pennsylvania. Founder ... to deliver the latest data to world leaders in ... brings together leaders at the forefront of the industry ... imaging. "The quality of the imaging ...
Breaking Biology News(10 mins):
(Date:3/27/2017)... YORK , March 27, 2017 ... developing novel therapies for neurodegenerative diseases, including Alzheimer,s ... that its application to list the Company,s common ... approved by The NASDAQ Stock Market, a unit ... the listing, Neurotrope will ring the Opening Bell at ...
(Date:3/24/2017)... , March 24, 2017  Infectex Ltd., a ... today announced positive results of a Phase 2b-3 clinical ... regimen in patients with multidrug-resistant pulmonary tuberculosis (MDR-TB). SQ109 ... at Sequella, Inc. ( USA ) and ... A total of 140 patients were enrolled in a ...
(Date:3/24/2017)... Biotech Ltd. ("Sinovac" or the "Company") (NASDAQ: SVA), a leading provider ... that its board of directors has amended its shareholder rights plan. The ... 2017 to March 27, 2018. The amendment was not in response to ... ... Ltd. is a China -based biopharmaceutical company that ...
(Date:3/24/2017)... VILLAGE, Calif. , March 24, 2017   ... dermatology and aesthetics company, today announced that Richard ... Officer, effective March 24.   Peterson, who brings ... succeed John Smither , who is retiring at ... Sienna in an advisory capacity. Peterson joins Sienna from ...
Breaking Biology Technology: