The alula is a small structure that is found on birds. It is located at the joint between the hand wing and the arm wings of birds and it is the freely moving, first digit of a bird's wing. It is normally used by birds in slow flight. In humans, the structure that is comparable to the alula is the thumb.
Answer:
Both of these are correct
moves constantly between Earth's surface and the atmosphere
and it is matter that is essential for life
no because she is trying to help not hurt
Answer:
c.reflects evolutionary history.
Explanation:
The best classification system in biology is that that reflects evolutionary history, this is because more developed animals evolved from ancestors, this means that little modifications on the DNA happened over the course of million of years that created the animals that we know today, so this little differences would be relfected on a classification system.
Some of the main causes are plant growth and ice wedging.