Nope... I don't remember when it did but no
Answer:
In terms of genetic variation, allelic richness (A) estimated through rarefaction resulted in 1.6–3.0 mean alleles per colony, and no private alleles were found. Mean genetic diversity (HE) was 0.525 (SD = 0.11), with values ranging from 0.276 (SD = 0.25) to 0.618 (SD = 0.09).
Explanation:
Utah prairie dog (Cynomys parvidens), and Mexican prairie dog (Cynomys mexicanus)—all of which may be considered rare (Hoogland 2006a). After 200 years of shootings, poisonings, conversion of habitat, and more recently plague, prairie dog numbers are a fraction of what they once were. Two of the species (Utah and Mexican) are listed as threatened or endangered under the Endangered Species Act (ESA).
Answer:
D.) If the homozygous tall plant (TT) crosses with a homozygous short plant (tt), then all the F1 plants become heterozygous tall plants (Tt).
Explanation:
Homozygous indicates that the alleles in the genotype are the same. Therefore, the genotype for homozygous tall plants is (TT) and the genotype for homozygous short plants is (tt).
After performing a cross, we know that all of the children will have the heterozygous genotype (Tt).
The process where a specie develops and evolves into new many species is termed as speciation. Macroevolution explores the mechanism of speciation where organisms across biological populations evolve as distinct population.
There are many causes to speciation, a) geographic isolation, b) gene flow reduction, and c) reproductive isolation.
Answer:
Until recent history,extinctions have always happened gradually and on a small scale.
Explanation:
Extinction occur when environmental factors like natural disaster,habitat fragmentation,over exploitation,global change don't favor the survival of species thus gradually leads to extinction of species.
Some times human activity becomes the major problem for extinction.More over,poor reproduction,decline in population number and genetic inbreeding also leads to extinction.
99% of all species that exist on earth become disappeared.
Evolution leas to speciation which leas to formation of new species but species become extinct when they are unable to survive against competition.