Biologists say that the annual migration of monarch butterfly from North America to Mexico is determined by a pattern of circulating genes on these butterflies.
Watching animals in the wild world is an interesting experience, even more interesting when witnessing them gather to migrate.
The golden frog festival in Panama, the giant anteater that prey ... is the most impressive animal images last week.
Monkeys feed on the streets, swans in the cold lake, princess butterflies on trees ... are the most beautiful animal images of the past week.