HOME >> BIOLOGY >> NEWS
Nevada researcher re-ignites mammal reproduction debate

One of the most debated hypotheses in evolutionary biology received new support today, thanks to a study by a scientist at the University of Nevada, Reno. Elissa Cameron, a mammal ecologist in the Department of Natural Resources and Environmental Science, has helped to disprove critics of a scientific theory developed in 1973.

At that time, ecologist Bob Trivers and mathematician Dan Willard said that large healthy mammals produce more male offspring when living in good conditions, such as areas where there is an ample food supply. Conversely, female mammals living in less desirable conditions would tend to have female offspring.

According to Cameron, the hypothesis demonstrated the idea that having more male offspring leads to greater evolutionary success for mammal parents, if living conditions support larger populations. Should conditions be less desirable, having female offspring would be a better investment for mammal parents.

"Male zebras can father more than a hundred offspring in a lifetime, whereas female zebras are constrained to minimal reproductive rates--about one a year," Cameron said. "Sons, therefore, offer higher breeding rates to zebra parents, while female offspring are a lower-risk investment.

"Therefore, if the animal's living conditions aren't suitable, giving birth to a female would better ensure the animal's genetic success in the long term. Daughters of less healthy mothers would out-reproduce sons in poorer conditions because males that are unsuccessful in having mates have few offspring while most females breed throughout their lifetime."

The problem with this idea is that, until now, only about 30-percent of studies have supported the hypothesis, which has been debated because there have been so many studies that have attempted to test the idea. The results have been contradictory--some find support for the hypothesis, some do not, Cameron said.

But in a journal article published toda
'"/>

Contact: Bob Conrad
bconrad@unr.edu
775-784-4724
University of Nevada College of Agriculture, Biotechnology, and Natural Resources
23-Aug-2004


Page: 1 2 3

Related biology news :

1. New clues emerge about the fate of smog in Sierra Nevada forests
2. Belgian researchers explore revolutionary approach to angiogenesis
3. Award winning researchers reveal potential new role for Glivec
4. University of Alberta researcher looks for clues to mysterious disease
5. $7.5 Million grant to Yale researchers for role of viruses in cancer
6. New anti-inflammatory strategy for cancer therapy identified by UCSD researchers
7. Joslin researchers clarify mechanisms for beta-cell formation
8. Pioneering AIDS researcher to speak at UH
9. Defensive action by influenza viruses demonstrated by Hebrew university researcher
10. Virginia Tech researchers to release findings on Smith River Project
11. Molecular motor myosin VI moves hand over hand, researchers say

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/14/2017)... (NYSE: IBM ) is introducing several innovative partner startups ... collaboration between startups and global businesses, taking place in ... nine startups will showcase the solutions they have built with ... France is one of the ... percent increase in the number of startups created between 2012 ...
(Date:5/16/2017)... 16, 2017   Bridge Patient Portal , ... MD EMR Systems , an electronic medical ... GE, have established a partnership to build an ... the GE Centricity™ products, including Centricity Practice Solution ... These new integrations will allow healthcare delivery ...
(Date:4/19/2017)... New York , April 19, 2017 ... competitive, as its vendor landscape is marked by the ... the market is however held by five major players ... Safran. Together these companies accounted for nearly 61% of ... of the leading companies in the global military biometrics ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... ... October 12, 2017 , ... ... platform specifically designed for life science researchers to analyze and interpret datasets, ... Franklin, who made a major contribution to the discovery of the double-helix ...
(Date:10/11/2017)... ... ... Personal eye wash is a basic first aid supply for any work environment, but most ... you rinse first if a dangerous substance enters both eyes? It’s one less decision, and ... unique dual eye piece. , “Whether its dirt and debris, or an acid or alkali, ...
(Date:10/11/2017)... , Oct. 11, 2017  VMS BioMarketing, a leading ... a nationwide oncology Clinical Nurse Educator (CNE) network, which will ... need for communication among health care professionals to enhance the ... nurses, office staff, and other health care professionals to help ... breast cancer. ...
(Date:10/11/2017)... ... October 11, 2017 , ... ... implantation and pregnancy rates in frozen and fresh in vitro fertilization (IVF) ... and maternal age to IVF success. , After comparing the results from the ...
Breaking Biology Technology:
Cached News: