Navigation Links
Older killer whales make the best mothers

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
BioMed Central

Page: 1 2

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:
(Date:10/8/2015)... , 8. Oktober 2015 ... global tätiges Unternehmen des Bereiches Tracking, hat ... mit der Gefängnisbehörde Virginias (Department of Corrections ... elektronische Überwachungsdienste für alle Strafen geliefert werden, ... Cassell , Präsident für den Amerikanischen Kontinent ...
(Date:10/7/2015)... 8, 2015 --> ... Cards (FPC) during third quarter 2015 amounted to around 960 ... 860 MSEK that was communicated 20 August 2015. ... delivery capacity and a continued growing demand for the company,s ... to be higher than during the third quarter. The revenue ...
(Date:10/6/2015)... Oct. 6, 2015 Track Group, Inc. (OTCQX: ... it has signed a contract with the Virginia Department ... full range of sentences under the Department,s oversight. ... Americas. "This contract with the Virginia DOC will expand ... and advances our position as a trusted leader in ...
Breaking Biology News(10 mins):
... commends President George W. Bush for asking Congress to ... physical sciences in his State of the Union address ... how paramount funding into basic research is to keeping ... Russ Lefevre said. "Much of our nations economic growth ...
... of complex, three-dimensional nanoscale structures and the ability ... now possible with a process developed by researchers ... the rapid evaporation of solvent from simple inks, ... nanofibers, stacked arrays of nanofibers and continuously wound ...
... Journeying to Johannesburg to survey bat colonies? To Kenya to ... about Roman ruins in Britain? Snowflakes in North America? ... an entire digital database of weird and wacky but ... matter. And that includes French cheese, purposeful knots and English ...
Cached Biology News:
(Date:10/9/2015)... and ROCKVILLE, Md. ... ("ITI"), a privately-held biotechnology company developing next generation ... that it has entered into an exclusive worldwide ... products for the treatment or prevention of any ... of the agreement, Immunomic Therapeutics will receive an ...
(Date:10/9/2015)... ... October 09, 2015 , ... Leading microbial genomics startup uBiome today launched the ... relationship between weight management and the microbiome. The study uses the ResearchKit framework, designed ... iPhone app. , The uBiome app is available as a free download from the ...
(Date:10/8/2015)... 2015  Genetic testing for mutations beyond those currently ... more couples at risk of having a child with ... the 2015 American Society of Human Genetics (ASHG) Annual ... Baltimore, Maryland . The study is one of ... ) are presenting at the conference this week demonstrating ...
(Date:10/8/2015)... Maryland , October 8, 2015 ... .   --> Goldman Small ... in the small cap and microcap sectors, announced ... research report on PharmaCyte Biotech, Inc. (OTCQB - ... focused on developing and preparing treatments for cancer ...
Breaking Biology Technology:
... Switzerland, Nov. 16, 2010 Syngenta has announced the ... from Australia, Zoltan Balogh from Hungary and Mario Pereda ... vouchers of $8000, $5000 and $3000, respectively. The winning ... based upon their quality, creativity and interpretation of Syngenta,s ...
... Nov. 16, 2010 Ingenuity® Systems, a ... science researchers, today announced a new collaboration ... predictive disease network research.  Under the collaboration, ... software, and the Ingenuity® Knowledge Base of ...
... 15, 2010 /PRNewswire-Asia-FirstCall/ -- 3SBio Inc. (Nasdaq: ... biotechnology company focused on researching, developing, manufacturing and marketing ... the third quarter ended September 30, 2010. ... Total net revenues increased by 24.9% over ...
Cached Biology Technology: