brawn v brains looks v loyalty
Last Updated : GMT 09:07:40
Egypt Today, egypt today
Egypt Today, egypt today
Last Updated : GMT 09:07:40
Egypt Today, egypt today

Nature's tradeoffs

Brawn v. brains, looks v. loyalty

Egypt Today, egypt today

Egypt Today, egypt today Brawn v. brains, looks v. loyalty

Pangolins, porcupines and hedgehogs
Paris - Arab Today

Biologists assessing the natural world sometimes sometimes sound like hard-nosed executives weighing the costs and benefits of an investment opportunity.

Species, they reason, can't be endowed with every possible trait.

Instead, they get the ones that help them to survive and hand on their genes, even if this comes at a cost.

Two studies published Wednesday by Britain's Royal Society shed light on these intriguing natural tradeoffs.

Examining 647 types of mammals, Theodore Stankowich and Ashly Romero from California State University Long Beach discovered that species boasting impressive protective gear were also not the brightest of beasts.

Pangolins, porcupines and hedgehogs, to name a few, can pretty much go about their business without worrying if they will wind up as some carnivore's midnight snack.

Needle-sharp quills or armour provide excellent protection against predators... except, notably, Homo sapiens. 

"The armadillos..., cooked without their cases, taste and look like a duck," Charles Darwin noted in his diary in 1832. "Very good."

But there is an evolutionary price to be paid for all that defensive apparatus.

"Their bearers may accrue extensive production and maintenance costs," Stankowich and Romero write in the journal Proceedings B, sounding rather like industrial analysts.

"Defended species," they concluded bluntly, "become less intelligent." 

Other mammals covered by no more than an insulating coat of fur cannot afford to be as carefree as their armoured cousins.

But, despite their vulnerability, these species have an advantage.

They are far better at detecting potential threats and fleeter of fleet of foot in escaping them.

Most critically, they also evolved bigger brains to manage all those tasks, the study found.

Again, that advantage came at a cost: brain power is "extremely energetically expensive," which means the animal has to eat more food, or eat food that is more energy-dense.

The only exceptions to the "either/or" rule, the authors found, were some tree-dwelling animals that had developed both bigger brains and some protective apparatus.  

Navigating branches, they hypothesised, would be difficult for the slow-witted.

- Mating game -

In the other study, Jenelie Dowling of the University of Montana and Michael Webster of Cornell University uncovered a surprising example of how sexual selection -- the other engine of evolutionary change -- shapes strategies within a single species.

They looked at the Australian red-backed fairy wren, Malurus melanocephalus to ornithologists.

These wrens are socially monogamous, which means they hang out in pairs.

But when it comes to sexual behaviour, males have a choice: be loyal or play the field.

If they couple with as many females as possible, they multiply the chances of progeny -- but there's a downside to doing so. 

The offspring from a fickle father are more at risk, because they lack a male parent who will defend their territory and protect the mother.

Loyalty, on the other hand, will produce fewer offspring, but the fledglings will have a better chance of survival

The study, published in the Royal Society's Biology Letters, used observation and experiments to show how male wrens use their looks to determine this mating strategy.

Males with more colourful plumage -- a sign of fitness -- are more likely to be nest-hoppers, and therefore sire more offspring but at a higher risk of mortality, they found.

Drabber males, though, are more inclined to stick to a single mate... if they are lucky enough to find one.

Source: AFP

egypttoday
egypttoday

Name *

E-mail *

Comment Title*

Comment *

: Characters Left

Mandatory *

Terms of use

Publishing Terms: Not to offend the author, or to persons or sanctities or attacking religions or divine self. And stay away from sectarian and racial incitement and insults.

I agree with the Terms of Use

Security Code*

brawn v brains looks v loyalty brawn v brains looks v loyalty



GMT 15:49 2011 Friday ,10 June

Oil firm wins injunction against Greenpeace

GMT 10:27 2015 Monday ,06 July

Mini to launch ‘Clubman’ in 2016

GMT 17:21 2011 Wednesday ,23 February

Lampard Desperate To Win The Champions League

GMT 10:13 2018 Tuesday ,09 January

Barcelona to unveil 160m Coutinho

GMT 23:03 2017 Monday ,16 January

Bank of Korea: Money Production Cost Rise in 2016

GMT 20:33 2011 Friday ,06 May

Asad\'s army arrests all men over 15 in Daraa

GMT 11:55 2011 Tuesday ,29 November

Ultrabooks could save the PC

GMT 13:02 2012 Saturday ,01 September

Zombies and Morons compete

GMT 07:31 2017 Tuesday ,20 June

Sisi keen on attaining unity

GMT 11:50 2015 Saturday ,26 September

The Library of Fragrance announces January launches

GMT 06:28 2014 Saturday ,18 October

Asian Junior Volleyball tourney kicks off in Bahrain
 
 Egypt Today Facebook,egypt today facebook  Egypt Today Twitter,egypt today twitter Egypt Today Rss,egypt today rss  Egypt Today Youtube,egypt today youtube  Egypt Today Youtube,egypt today youtube

Maintained and developed by Arabs Today Group SAL.
All rights reserved to Arab Today Media Group 2021 ©

Maintained and developed by Arabs Today Group SAL.
All rights reserved to Arab Today Media Group 2021 ©

egypttoday egypttoday egypttoday egypttoday
egypttoday egypttoday egypttoday
egypttoday
بناية النخيل - رأس النبع _ خلف السفارة الفرنسية _بيروت - لبنان
egypttoday, Egypttoday, Egypttoday