IELTS Reading: gap-fill summary
Read the following passage about animal migration.
(Source: National Geographic)
Large migrations are some of nature's greatest spectacles. Wildebeest and zebra chase the rains through the Mara ecosystem every year, monarch butterflies trace a path from Mexico to Canada and back, and tiny songbirds fly nonstop for days at a time. And now scientists are starting to figure out how they know where to go, and when.
Some of these animals, they’ve found, have their migration pathways written into their genes. A songbird hatched in a laboratory, having seen nothing of the natural world, still attempts to begin migration at the right time of year and in the right cardinal direction.
But large mammals like bighorn sheep and moose are a different story. Wildlife researchers have long suspected that they require experience to migrate effectively, that their annual journeys are the result of learning from one another, not of genetic inheritance. A new study, published Thursday in the journal Science, suggests that those hunches may be correct—some animals must learn how to migrate.
The existence of collective information and knowledge, that can be passed from older animals to younger ones, is a form of “culture,” researchers explain. And when animals learn as a result of social interaction and the transfer of this information, that’s a type of cultural exchange—as opposed to genetic.Fill each gap in the summary below with ONE word from the passage.
Scientists believe that __
are responsible for some animal migrations. Songbirds, for example, do not need to learn when and in which __
to migrate. On the other hand, bighorn sheep appear to __
migration habits from the herd. They, and other mammals, seem to have a __
that is passed from one generation to the next through interaction and exchange of __