Directional selection I'm pretty sure hope it helps!
Answer:
Some challenges animals might face when migrating are disease, global climate change, overexploitation, and habitat destruction.
Explanation:
In virtually every corner of the globe, migratory animals face a growing array of threats, including habitat destruction, overexploitation, disease, and global climate change. Saving the great migrations will be one of the most difficult conservation challenges of the 21st century.
Answer: The whole surface of Earth is a series of connected ecosystems. Ecosystems are often connected in a larger biome. Biomes are large sections of land, sea, or atmosphere. Forests, ponds, reefs, and tundra are all types of biomes, for example. They're organized very generally, based on the types of plants and animals that live in them. Within each forest, each pond, each reef, or each section of tundra, you'll find many different ecosystems.
Explanation: Hope this helps :)
Answer:
When the salt water is mixed with fresh water,it is called brakish water which have the salinity 0.5 to 35 ppt.
Explanation:
The mixing of fresh and salt water is important for aquatic organisms.
The catadromous fish born in marine habitat but they spend their rest of life in the fresh water where growing and maturation takes place.
Ex- Eel is the common example of catadromous fish.
Like wise,
Anadromous fish born in fresh water and spends their life in the sea and return to fresh water for spawning.
For example Salmon, smelt, shad, are common examples.
Thus mixing of water is important for breeding and growing of these fishes.
More over, the brakish water contain world's most diversified life forms.
ANSWER:C) farming and hiking