Navigation Links
Older killer whales make the best mothers
Date:2/3/2009

Killer whales (Orcinus orca) nearing the menopause may be more successful in rearing their young. New research published in BioMed Central's open access journal Frontiers in Zoology shows that estimated survival rates for calves born to these older mothers were 10% higher than those for other calves.

Eric Ward from the Northwest Fisheries Science Center, Seattle, USA, coordinated a team of researchers who studied killer whales inhabiting the inland and nearshore waters of Washington state (USA) and British Columbia (Canada). They used a 30-year dataset collected by the Center for Whale Research and Canada's Department of Fisheries and Oceans. He said, "During annual photographic surveys, nearly every individual in the population has been recorded. Each animal has unique pigmentation, scars, and fin shapes, allowing us to track the survival and reproductive performance of each female over time".

The authors aimed to investigate what benefits killer whales derive from the menopause. One theory, termed the "attentive mother hypothesis", is that giving birth to calves and then losing the ability to reproduce helps the mother to focus on bringing up her offspring, without wasting time and energy on further pregnancies. The authors' results support this theory to an extent in that during a calf's first year of life, having a mother who was nearing menopause increased chances of survival. According to Ward, "We found that the oldest mothers may also be the best mothers. Older females may be more successful in raising young because of maternal experience, or they may allocate more effort to their offspring relative to younger females".

Killer whales are extremely long lived, with one female believed to be more than 90 years old. Males rarely live past 50, but female life expectancy is considerably longer. Females can produce their first calf as early as age 10, and continue to produce offspring until their early 40s.


'/>"/>

Contact: Graeme Baldwin
graeme.baldwin@biomedcentral.com
44-020-707-94804
BioMed Central
Source:Eurekalert

Related biology news :

1. Gardening gives older adults benefits like hand strength and self-esteem
2. Gardening gives older adults benefits like hand strength and self esteem
3. Research finds older women who are more physically fit have better cognitive function
4. Pain is in the eyes of the beholder
5. Older people who diet without exercising lose valuable muscle mass
6. BIO-key(R) Issues Open Letter to Shareholders
7. Testosterone replacement theraphy beneficial in men 60 and older
8. RING finger protein 5 may guide treatment for muscle disease in older adults
9. Stakeholders use science to find common ground on wood supply from forests
10. Worlds largest investor coalition seeks further disclosure on climate change and shareholder value
11. High blood pressure in older adults traced to genes effects in blood vessels
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/13/2017)... UBM,s Advanced Design and Manufacturing event in ... and evolving technology through its 3D Printing and Smart ... the expo portion of the event and feature a ... on trending topics within 3D printing and smart manufacturing. ... will take place June 13-15, 2017 at the Jacob K. ...
(Date:4/11/2017)... 11, 2017 No two people are ... the New York University Tandon School of Engineering ... found that partial similarities between prints are common ... mobile phones and other electronic devices can be ... vulnerability lies in the fact that fingerprint-based authentication ...
(Date:4/5/2017)... , April 5, 2017 Today HYPR ... that the server component of the HYPR platform is ... providing the end-to-end security architecture that empowers biometric authentication ... HYPR has already secured over 15 million users across ... manufacturers of connected home product suites and physical access ...
Breaking Biology News(10 mins):
(Date:9/21/2017)... ... September 21, 2017 , ... Executives ... the world’s most progressive pharma and biotech organizations to do more clinical trials ... and biotech events in Q4. , DrugDev will demonstrate DrugDev Spark™, the world’s ...
(Date:9/21/2017)... DIEGO, CALIF. (PRWEB) , ... September 21, 2017 , ... ... earlier this month. The organization, a worldwide society of professional women with high ... venue to hold its annual dinner. , Twelve members began with an ...
(Date:9/20/2017)... ... September 20, 2017 , ... ... appointed Vishwas Paralkar to the role of chief scientific officer. In this role, ... report to Cybrexa’s president and CEO, Per Hellsund. , “I was impressed with ...
(Date:9/20/2017)... ... September 20, 2017 , ... Proscia Inc. ... , a provider of whole slide imaging solutions, are hosting a pre-conference workshop ... entitled “Successfully Deploying a Best-in-Class Strategy for Digital Pathology,” will feature Proscia CEO, ...
Breaking Biology Technology: