Sentences with phrase «beak shape»

"Beak shape" refers to the physical form or structure of a bird's beak or bill. It describes the size, length, width, and curvature of a bird's beak. Full definition
Adaptationism certainly appears to hold true in microevolution — small - scale evolutionary change within species, such as changes in beak shape in Galapagos finches in response to available food sources.
There were also strong similarities with genes identified with beak shape in Darwin's study of finches — one of the best - known examples of how physical traits have adapted to different environments in the wild.
Two species of finch in the Galápagos Islands diverged in beak shape as they adapted to different food sources.
Working with DNA samples collected by the Grants, researchers at Uppsala identified the gene that influences beak shape by comparing the genomes of 120 birds, all members of the 15 species known as «Darwin's finches.»
Parrots have a characteristic curved beak shape with the upper mandible having slight mobility in the joint with the skull and a generally erect stance.
If beak shape changes, he reasoned, it might mean that the bird can't sing the same old song — just as a flute and a tuba sound different.
But beak shape didn't seem to play a role in surviving the drought, the team found.
Individuals from a species with a highly variable beak shape — the medium ground finch (Geospiza fortis)-- had a mixture of the blunt and pointed gene variants.
By looking at closely related finches that have different beak shapes, the researchers were able to pinpoint the genes responsible for beak morphology.
In a previous study from the same team the ALX1 gene was revealed to control beak shape (pointed or blunt) and now a gene (HMGA2) affecting beak size has been identified.
A team of scientists from Uppsala University and Princeton University, led by Leif Andersson at SciLifeLab in Uppsala, has now shed light on the evolutionary history of Darwin's finches and have identified a gene that explains variation in beak shape within and among species.
The team found that the most unusual beak shapes often emerged over relatively short periods and therefore involved exceptionally fast evolutionary change.
By combining the information from DNA - based evolutionary trees, the research team were able to infer ancestral beak shapes as well as rates and patterns of beak evolution stretching back more than 100 million years.
Researchers from Princeton University and Uppsala University in Sweden have identified a gene in the Galápagos finches studied by English naturalist Charles Darwin that influences beak shape and that played a role in the birds» evolution from a common ancestor more than 1 million years ago.
Cockatoos share many features with other parrots including the characteristic curved beak shape and a zygodactyl foot, with two forward toes and two backwards toes.
In the finches, the gene displayed two distinct variants that matched up neatly with beak shape.
A wonderfully produced show, but at one point the narrator discusses a particular species on one island where the male has a beak shaped like one particular flower, and it could not feed on the same flower as the female, which has a beak that fits another flower on the same island.
Very thinly slice the carrot into strips, then cut into feet, wings and beak shapes.
I cut the pipe cleaner into quarters and then cut a beak shape and a stripe for the neck from some leftover felt.
The specimen studied by Longrich was too incomplete to identify the exact species accurately, but showed a strange twist to the jaw, causing the teeth to curve downward and outwards in a beak shape.
During the past four decades, the Grants and their research team have found that beak shape and size played a significant role in the evolution of finch species via natural selection when droughts hit Daphne Major in 1977, 1985 and 2004.
Like Charles Darwin's famous finches, which evolved a wide range of beak shapes and sizes to exploit the different foods available in the Galápagos Islands, these cichlids represent a textbook example of what biologists term an adaptive radiation — the phenomenon whereby one lineage spawns numerous species that evolve specializations to an array of ecological roles.
«This is very reminiscent of the famous case of Darwin's finches on the Galapagos, which show remarkable variation in their beak shapes.
During the time that has passed the Darwin's finches have evolved into 18 recognized species differing in body size, beak shape, song and feeding behaviour.
Ask students to put the puzzle pieces together and identify each bird, focusing on markings and shape, such as head shape, body shape, beak shape, legs, eyes, and tail.
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