Mutation, genetic recombination, and gene flow all add what to a population

The answer is; genetic diversity

Genetic diversity is the number of genetic characteristics in a population. Genetic diversity is important in a population especially in its adaptability to a changing environment.   The diversity is acted upon by natural selection and enables the population to evolve with the changing environment.

answer: dinosaur

explanation

their extinction was caused by massive asteroid that fell on earth

answer: grassland biomes are closer to the equator and receive more rain.

grasslands are biomes that are dominated by grasses rather shrubs and trees. savanna are biomes that exhibit grasses, shrubs and small tree as vegetation. grasslands are located near the equator of the earth. these are found in north america. savanna biomes are found in africa, south america, australia and india. grassland exhibit moderate climatic conditions, it receives   amount of rainfall higher than savanna.   therefore, savanna exhibit dry and hot climatic conditions.