Дайте вдповд на запитання1.How do biologists usually define ichthyology?2. What branch

Дайте вдповд на запитання
1.How do biologists usually define ichthyology?
2. What branch of zoology has a long documented history? 3.When and where did the first vertebrates evolve? 4.Were the first fish like modern fish?
5. How many species of fish exist in nature?
6.What do you know about body shapes and sizes of fish? 7. What is the maximum size of fish?
8.What organ has the highest energy and oxygen demand? 9.What tendency do tropical fish show?
10.Describe the reasons why people keep fish in aquaria. 11.What do you know about feeding habits of fish?
12. What do fish usually produce?