ROBO1 may be related to those mental skills. From studies of humans, we know that ROBO1 is involved with brain development. Different versions of ROBO1 affect how the brain works and learns. For example, having a certain version of ROBO1 seems to contribute to dyslexia, a condition where people have trouble reading. This led to the hypothesis that the A version of the gene was favored by artificial selection in breeds in which humans desired traits that lead to high agility.
To assess agility, the team used records of which breeds were entered in agility competitions and which breeds actually won agility titles.
For each breed, they calculated the number of titles won per dog of that breed entered in competition. They then divided breeds into eight groups according to how likely each breed was to win agility titles:.
Top performers such as Border Collies and Pumis, both herding dogs were in the red group. Breeds that never or very rarely won agility competitions like the Greyhound and Anatolian Shepherd were in the blue group. They found ROBO1 data for dogs of breeds in one of the eight breed groups.
These were not dogs that had necessarily competed in agility trials themselves; they were just dogs that were members of the same breeds as competitors. For each of the eight breed groups, the team calculated how common the A gene version of ROBO1 was compared to other gene versions. Here is what they found:. On this graph, the x -axis orders the eight breed groups from least likely to win agility titles far left to most likely far right.
The y -axis shows how common the A gene version is in that group. So, for example, a frequency of 0. R 2 indicates how well the frequency of different gene versions is explained by the breed group. An R 2 of 0 would indicate that breed group cannot predict the frequency of the A gene version at all. An R 2 of 1 would indicate that one can precisely predict the frequency of the A gene version based on breed group.
In this case, the R 2 value of 0. These findings further support the hypothesis that the A version of ROBO1 was under strong artificial selection by humans in breeds for which humans desired traits that lead to strong agility. Now researchers can build on this hypothesis to learn exactly how the A version of ROBO1 impacts dogs that carry it, why the A gene version was favored in some breeds but not others, and importantly, how this might be related to athletic performance and other traits in humans.
She wanted to be a scientist. So Elaine forged her own path. You cannot download interactives. In the mids, Charles Darwin famously described variation in the anatomy of finches from the Galapagos Islands. Alfred Russel Wallace noted the similarities and differences between nearby species and those separated by natural boundaries in the Amazon and Indonesia.
Independently they came to the same conclusion: over generations, natural selection of inherited traits could give rise to new species. Use the resources below to teach the theory of evolution in your classroom. Natural selection is the process through which species adapt to their environments.
It is the engine that drives evolution. Charles Darwin and Alfred Wallace developed the idea of evolution through natural selection. But this idea was not accepted by scientists until more evidence came along. Use this infographic to explore how Darwinism and genetics came together to explain what we know today about evolution. Join our community of educators and receive the latest information on National Geographic's resources for you and your students.
Skip to content. Image pigeons Like many animals kept in human captivity, mating pairs of pigeons are often paired together based on their genetics to achieve the most desirable traits in their offspring.
Photograph by Mark Thiessen. Twitter Facebook Pinterest Google Classroom. Encyclopedic Entry Vocabulary. Media Credits The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. Media If a media asset is downloadable, a download button appears in the corner of the media viewer.
Text Text on this page is printable and can be used according to our Terms of Service. Interactives Any interactives on this page can only be played while you are visiting our website. Related Resources. Image credit: Genome Research Limited. Purebred dogs like the Labrador Retriever were originally established through many generations of inbreeding. Image credit: PetsNerd. The Labradoodle is a crossbred dog resulting from breeding a Labrador with a poodle. GMOs are organisms that have had their characteristics changed through the modification of their DNA.
In biology, evolution is the change in the characteristics of a species over several generations and relies on the process of natural selection. A model organism is a species that has been widely studied, usually because it is easy to maintain and breed in a laboratory setting and has particular experimental advantages. Humans have been breeding animals for millenia to bring out desirable characteristics.
With the thoroughbred race horse there's lots of money at stake but with research mice it's the possibility of life-saving new treatments.
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