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I would just like to say that Phil Gasper is my favorite read on this list.

Charlie

Phil Gasper wrote:
> We're biological creatures, so trivially there is a biological basis 
> for everything we do, because everything we do is compatible with our 
> biology. Lions forming prides has about as much to do with US 
> imperialism as aphids living with ants has to do with the 
> transatlantic slave trade. --PG
>
> Sent from my iPod
>
> On Jun 29, 2009, at 15:42, Michael Balter <[log in to unmask] 
> <mailto:[log in to unmask]>> wrote:
>
>> More on behavior that humans share with some other animals. How 
>> likely is it that there is no biological basis to human warfare and 
>> the human tendency to band into groups and fight other groups for 
>> territory and resources, even if it is channeled culturally?
>>
>> http://news.bbc.co.uk/earth/hi/earth_news/newsid_8120000/8120712.stm
>>
>> Lion prides form to win turf wars
>> Matt Walker
>> Editor, Earth News
>>
>> * Lions form prides to defend territory against other lions, not to 
>> improve their hunting success, a study reveals. *
>>
>> In doing so, they act much like street gangs, gathering together to 
>> protect their turf from interlopers, says a leading lion expert.
>>
>> The bigger the gang, the more successful the lions are, information 
>> that could help conserve wild lions.
>>
>> The discovery helps explain why lions, uniquely among the cat 
>> species, live together in social groups.
>>
>> Lions stand out amongst all the cat species for their gregarious nature.
>>
>> Across Africa and Asia, lions form prides of varying sizes comprising 
>> one or more males and often numerous females and cubs.
>>
>> * The bigger the gang, the more successful it is at controlling the 
>> best areas. *
>> Lion expert Craig Packer
>>
>> But why they do so has remained a mystery. A long-standing idea is 
>> that female lions socialise in order to hunt cooperatively. But 
>> despite the common sight of multiple females working together to 
>> outflank and bring down large prey, there is no clear link between 
>> how many lions hunt together and their hunting success.
>>
>> Another is that lions gather to protect territory. Indeed, a range of 
>> animals from social insects to primates form social groups that 
>> defend territories against competitors.
>>
>> But while there has been anecdotal evidence that bigger groups have a 
>> competitive advantage, the idea has never been rigorously tested over 
>> long periods of time.
>>
>> That has now changed with a study analysing the behaviour of 46 lion 
>> prides living in the Serengeti National Park, Tanzania.
>>
>> * 'Street gangs' *
>>
>> Conducted by ecologists Anna Mosser and Craig Packer of the 
>> University of Minnesota in St Paul, US, the study collated data about 
>> the prides' behaviour over 38 years, including where they ranged, 
>> their composition and how they interacted.
>>
>> Mosser's and Packer's key finding was that competition between lion 
>> prides significantly affects the mortality and reproductive success 
>> of female lions, they report in the journal Animal Behaviour.
>>
>> Larger prides with more adult females not only produced more cubs, as 
>> might be expected, but the females within these prides were less 
>> likely to be wounded or killed by other lions.
>>
>> Prides with more females were also more likely to gain control of 
>> areas disputed with neighbouring prides, and those prides that 
>> recruited lone females improved the quality of their territory.
>>
>> "The most important way to think about this is that lion prides are 
>> like street gangs," says Packer.
>>
>> "They compete for turf. The bigger the gang, the more successful it 
>> is at controlling the best areas. The main difference from humans is 
>> that these are gangs of female lions."
>>
>> * Best 'real estate' *
>>
>> Both researchers think the study, alongside other work they have yet 
>> to publish, finally confirms that bigger prides form to defend 
>> territory.
>>
>> "The advantage of large group size for group-territorial animals has 
>> been suspected for a long time, but had never been proven with data," 
>> says Mosser. "With this paper, we were able to do just that because 
>> of the many groups studied over a long period."
>>
>> One surprise revealed by the research is that male lions turn out to 
>> play a much bigger role in how prides interact than expected.
>>
>> LION FAMILY LIFE
>> # A lion pride is made of one to 21 females, their offspring, and a 
>> temporary coalition of 1 to 9 males
>> # One-third of female lions in the Serengeti leave their mother's pride 
>> to form a new one
>> # Males leave their pride by age 4, to go solo or form a coalition with 
>> other males
>>
>> Large coalitions of female lions are so successful at dominating 
>> small neighbouring prides that male lions step in to try to alter the 
>> balance of power. Males will often attack and attempt to kill female 
>> lions in neighbouring prides to tip the odds in favour of their own 
>> pride.
>>
>> "Males turn out to be playing a greater role than we realised," says 
>> Packer. "Males attack females from neighbouring prides, likely 
>> altering the balance of power in favour of 'their' females."
>>
>> The territorial advantages gained by coming together into larger 
>> social groups would have driven the evolution of social behaviour in 
>> lions, say the researchers.
>>
>> "It also confirms a pattern that is probably applicable for many 
>> species, including group-territorial ants, birds, and chimpanzees," 
>> says Mosser, who is now at The Jane Goodhall Institute, in Kigoma, 
>> Tanzania.
>>
>> Such insights will help with the conservation of lions, the numbers 
>> of which are suspected to have fallen by at least a third across 
>> Africa over the past two decades.
>>
>> The research shows that "the lions are competing for relatively 
>> scarce 'hotspots' of high value real estate," says Packer.
>>
>> So "lion numbers are ultimately limited by the number of hotspots 
>> that are safely inside national parks".
>>
>> Story from BBC NEWS:
>> http://news.bbc.co.uk/go/pr/fr/-/earth/hi/earth_news/newsid_8120000/8120712.stm
>>
>> Published: 2009/06/29 10:37:44 GMT
>>
>> © BBC MMIX
>>
>>
>>
>> -- 
>> ******************************************
>> Michael Balter
>> Contributing Correspondent, Science
>> Adjunct Professor of Journalism,
>> Boston University
>>
>> Email:           [log in to unmask] 
>> <mailto:[log in to unmask]>
>>
>> Website:       michaelbalter.com <http://michaelbalter.com>
>> Balter's Blog: michael-balter.blogspot.com 
>> <http://michael-balter.blogspot.com>
>> ******************************************