Why are competing or alternative explanations of scientific phenomena considered a strenght of science?

image result for describe the various types of gene mutationsghr.nlm.nih.gov

the types of mutations include: missense mutation: this type of mutation is a change in one dna base pair that results in the substitution of one amino acid for another in the protein made by a gene. nonsense mutation: a nonsense mutation is also a change in one dna base pair.

explanation:

what is this saying?

fossil's are like over rated rocks like low key not gonna lie i don't get why we can't just call them old rocks like for real i mean i call my grandpa and grandma that smh

1. is geographic distribution

2 is increasing complexity

3 is transitional forms