TEXTO:
Scientists claim to have solved the mystery of why
zebras have their characteristic black and white stripes.
There have been many theories to explain the
zebra’s unmistakable stripes. Scientists have suggested
[5] that each zebra has a unique pattern that lets other
animals recognize it. Or that the mass of black and white
∈a vast herd provides confusing camouflage that puts
off predators.
But the team that carried out the present study set
[10] out to test exactly what effect the stripes had on a zebra’s
most irritating and widespread enemy - the blood-sucking
horsefly. As part of their experiment the team put
sticky horse models — one white, one black and one
zebra-striped — into a fly-infested field. When they
[15] collected the flies that had landed and stuck to each of
the models, they found that the model zebra attracted
by far the fewest flies.
The researchers think that zebras had a blackcoated
ancestor, which evolved its white stripes ∈ an
[20] evolutionary arms race, with an insect that’s become
the biting, disease-carrying plague of most horse herds.
WHY zebras have stripes. Disponível em: http://www.telegraph.co.uk/ news/earth/wildlife/10737443/Why-do-Zebras-have-stripes-Scientistsclaim-to-have-the-answer.html. Acesso em: 12 out. 2015.
The ’s∈ “that’s become” (l. 20) is the
