How are genetic mutations caused and what effect can they have on an organism?

Some mutations don't have any noticeable effect on the phenotype of an

organism. This can happen in many situations: perhaps the mutation occurs

in a stretch of DNA with no function, or perhaps the mutation occurs in a

protein-coding region, but ends up not affecting the amino acid sequence of

the protein.

Hoping my answer works for you :)

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.

the match lol