Cross cultural studies or which can be called ethology is important in studying behavioral biology because ethology is the scientific and objective study of an animal well particularly focuses on its behavioral under natural conditions and viewing behavior as an evolutionary active trait. in some ways we can adopt the learning in this study to what we have.
Answer:
a process called fermentation
Answer:
The ecosystems are different
Explanation:
Every ecosystem needs most of the types, such as producers and herbivours, but different animals need different climates, such as cacti need deserts, yet fish need water, they can't( Or shouldn't ) Be in the same ecosystem due to thier needs.
Answer : (1) The correct option is, (A) increases
(2) The correct option is, (C) Decreases
Explanation :
Gravitational force : It is defined as the gravitational force is directly proportional to the product of the masses of the two object and an inversely proportional to the square of the distance between the two object.

where,
F = gravitational force or gravity
M and m = mass of two object
r = distance between the two object
G = gravitational constant
When the mass of an object increases then the gravitational force or gravity is increases because gravitational force is directly proportional to the mass of an object.
When the distance between the two object increases then the gravitational force or gravity is decreases because gravitational force is inversely proportional to the distance between the two object.
Hence, (1) As mass increases, gravity increases. (2) As distance increases, gravity decreases.
Answer:
1. human beings ,animals etc
2.Trees