Featured Research

from universities, journals, and other organizations

'Survival of the cutest' proves Darwin right

Date:
January 21, 2010
Source:
University of Manchester
Summary:
Domestic dogs have followed their own evolutionary path, twisting Darwin's directive "survival of the fittest" to their own needs -- and have proved him right in the process, according to a new study.

'Survival of the cutest.' Domestic dogs have followed their own evolutionary path, twisting Darwin's directive 'survival of the fittest' to their own needs.
Credit: iStockphoto/Aldo Murillo

Domestic dogs have followed their own evolutionary path, twisting Darwin's directive 'survival of the fittest' to their own needs -- and have proved him right in the process, according to a new study by biologists Chris Klingenberg, of The University of Manchester and Abby Drake, of the College of the Holy Cross in the US.

The study, published in The American Naturalist on January 20,  2010, compared the skull shapes of domestic dogs with those of different species across the order Carnivora, to which dogs belong along with cats, bears, weasels, civets and even seals and walruses.

It found that the skull shapes of domestic dogs varied as much as those of the whole order. It also showed that the extremes of diversity were farther apart in domestic dogs than in the rest of the order. This means, for instance, that a Collie has a skull shape that is more different from that of a Pekingese than the skull shape of the cat is from that of a walrus.

Dr Drake explains: "We usually think of evolution as a slow and gradual process, but the incredible amount of diversity in domestic dogs has originated through selective breeding in just the last few hundred years, and particularly after the modern purebred dog breeds were established in the last 150 years."

By contrast, the order Carnivora dates back at least 60 million years. The massive diversity in the shapes of the dogs' skulls emphatically proves that selection has a powerful role to play in evolution and the level of diversity that separates species and even families can be generated within a single species, in this case in dogs.

Much of the diversity of domestic dog skulls is outside the range of variation in the Carnivora, and thus represents skull shapes that are entirely novel.

Dr Klingenberg adds: "Domestic dogs are boldly going where no self respecting carnivore ever has gone before.

"Domestic dogs don't live in the wild so they don't have to run after things and kill them -- their food comes out of a tin and the toughest thing they'll ever have to chew is their owner's slippers. So they can get away with a lot of variation that would affect functions such as breathing and chewing and would therefore lead to their extinction.

"Natural selection has been relaxed and replaced with artificial selection for various shapes that breeders favour."

Domestic dogs are a model species for studying longer term natural selection. Darwin studied them, as well as pigeons and other domesticated species.

Drake and Klingenberg compared the amazing amount of diversity in dogs to the entire order Carnivora. They measured the positions of 50 recognizable points on the skulls of dogs and their 'cousins' from the rest of the order Carnivora, and analyzed shape variation with newly developed methods.

The team divided the dog breeds into categories according to function, such as hunting, herding, guarding and companion dogs. They found the companion (or pet) dogs were more variable than all the other categories put together.

According to Drake, "Dogs are bred for their looks not for doing a job so there is more scope for outlandish variations, which are then able to survive and reproduce."

Dr Klingenberg concludes: "I think this example of head shape is characteristic of many others and is showing it so clearly, showing what happens when you consistently and over time apply selection.

"This study illustrates the power of Darwinian selection with so much variation produced in such a short period of time. The evidence is very strong."


Story Source:

The above story is based on materials provided by University of Manchester. Note: Materials may be edited for content and length.


Journal Reference:

  1. Chris Klingenberg and Abby Drake. Large-scale diversification of skull shape in domestic dogs: Disparity and modularity. The American Naturalist, January 20, 2010

Cite This Page:

University of Manchester. "'Survival of the cutest' proves Darwin right." ScienceDaily. ScienceDaily, 21 January 2010. <www.sciencedaily.com/releases/2010/01/100120093525.htm>.
University of Manchester. (2010, January 21). 'Survival of the cutest' proves Darwin right. ScienceDaily. Retrieved August 22, 2014 from www.sciencedaily.com/releases/2010/01/100120093525.htm
University of Manchester. "'Survival of the cutest' proves Darwin right." ScienceDaily. www.sciencedaily.com/releases/2010/01/100120093525.htm (accessed August 22, 2014).

Share This




More Plants & Animals News

Friday, August 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Farm Resurgence Grows With Younger Crowd

Farm Resurgence Grows With Younger Crowd

AP (Aug. 22, 2014) — New England farms are seeing a surge in younger farm hands as the 'buy local' food movement grows across the country. (Aug. 22) Video provided by AP
Powered by NewsLook.com
Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) — An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Terrifying City-Dwelling Spiders Are Bigger And More Fertile

Terrifying City-Dwelling Spiders Are Bigger And More Fertile

Newsy (Aug. 21, 2014) — According to a new study, spiders that live in cities are bigger, fatter and multiply faster. Video provided by Newsy
Powered by NewsLook.com
Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Newsy (Aug. 21, 2014) — Russian cosmonauts say they've found evidence of sea plankton on the International Space Station's windows. NASA is a little more skeptical. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins