When traversing cluttered environments at nearly cruising speeds, birds need to be constantly aware of the distances to oncoming obstacles and the spaces between them to make split-second decisions about whether a gap can be traversed and to determine whether a change in the wing posture is necessary to facilitate an injury-free passage. Do birds fly through passages that are narrower than their wingspan? If so, what postural changes do they make to accommodate the passage? Seven budgerigars (Melopsittacus undulatus) were confronted with an aperture of variable width in the experiments. We aimed to investigate their flight maneuvers through the aperture and to enquire whether they display awareness of their body size.6 Mark For Review6Which choice best describes the function of the underlined sentence in the overall structure of the text?A) It implies that scientists will never be able to describe bird flight patterns with certainty. B) It introduces various elements of bird flight patterns that the researchers wanted to study. C) It discredits previous research on bird flight patterns, which relied on a flawed methodology. D) It shows that the scientific community frequently questions the relevance of bird flight patterns.

The flight patterns of two different bird species can vary greatly. For example, a hawk will soar high in the sky and swoop down to catch its prey __________ a sparrow usually stays close to the ground and flits from tree branch to branch. Hawks have large wings with long feathers that allow them to glide through the air more easily than sparrows which have shorter, rounder wings that help them maneuver quickly between obstacles. The differences in their physical features contribute significantly to how they navigate their environment while flying.

Have you ever watched a hummingbird sipping from a flower? These amazing little creatures are the only birds that can fly in every direction. They can also hover in one spot, much like a helicopter. Their wings can flap up to 80 times per second! Hummingbirds are so tiny you may think that they are large insects as they flap through the air. Some scientists believe that hummingbirds are a bridge between the insect and bird worlds. They have observed that hummingbirds flap their wings more like insects than birds. But don't think, just because they are tiny, that hummingbirds are weak. Hummingbird fossils from tens of millions of years ago have been discovered. Somehow these amazing thumb-sized marvels have survived a long, long time.From the text above, what can you conclude about Hummingbird. Choose the correct informationHummingbirds can stay in one place just like helicopters.  blankHummingbirds are family of insects because they can flap their wings. blankHummingbirds are the only birds that can fly in every direction. blankScientists have discovered a hummingbird thumb that is tens of millions of years old. blank     Χ           √

If these birds travel on an average speed of 350 km/ day, find out in how many days each of the species will take to complete the round trip.

The Grants were able to show that the changes in beak depth they observed in finches were due to genetic differences by determining that the beak size of parents was similar to the beak size of their

While researching a topic, a student has taken the following notes:• Each year, trillions of animals migrate by flying through the air.• Insects, such as mosquitos, butterflies, bees, locusts, and moths, are among the most common migratory animals.• It has been assumed that insects migrate in a random fashion, being heavily impacted by the changing winds.• Researchers from the Max Planck Institute of Animal Behavior led a study in which hawkmoths were tagged and monitored as they migrated from Germany to the Alps.• The study’s surprising results demonstrated that the hawkmoths have more sophisticated flight strategies than previously thought.25Mark for ReviewABCThe student wants to emphasize the study’s significance. Which choice most effectively uses relevant information from the notes to accomplish this goal?AIt has been assumed that insects migrate in a random fashion, so researchers from the Max Planck Institute of Animal Behavior studied the migratory habits of hawkmoths.BResearchers from the Max Planck Institute of Animal Behavior tagged and monitored hawkmoths, which, like mosquitos, butterflies, bees, and locusts, are migratory animals.CTrillions of animals migrate through the air each year; recently, one such animal was tagged and monitored.DThe study's surprising results demonstrated that rather than migrating in a random fashion, as was previously assumed, hawkmoths exhibit sophisticated flight strategies