The answer would be 3; theory! hope that helps
Answer:
common ancestry
Explanation
Common ancestry refers to the fact that two or more species have the same ancestor. Moreover, in genetics, sequence homology (either DNA or protein sequence homology) refers to common ancestry between different species/taxa (instead of sequence similarity, which may be caused by both convergent or divergent evolution). In bioinformatics, both local and global alignments of DNA/RNA/protein sequences can be used to determine sequence homology. Sequence homology due to common ancestry may be caused by three types of evolutionary events: 1-speciation (ortholog sequences), 2-duplication (paralog sequences), or 3-horizontal gene transfer (compared to speciation and duplication, horizontal gene transfer is an extremely rare evolutionary event).
Ocean currents are convection
Answer: A trait that is affected by many factors, both genetic and environmental, that enhance, halt, shape, or alter the expression of genes, resulting in a phenotype that may differ markedly from the genotype, is said to be MULTIFACTORIAL.
Explanation: Multifactorial inheritance may be presented by a model in which liability to a disorder is dependent on combination of genetic factor and environmental factor. Examples of trait with this mode of inheritance are neural tube defects, cleft lip and congenital dislocation of the hip.
Sympatric speciation is one of three traditional geographic modes of speciation.[2][3] Allopatric speciation is the evolution of species caused by the geographic isolation of two or more populations of a species. In this case, divergence is facilitated by the absence of gene flow. Parapatric speciation is the evolution of geographically adjacent populations into distinct species. In this case, divergence occurs despite limited interbreeding where the two diverging groups come into contact. In sympatric speciation, there is no geographic constraint to interbreeding. These categories are special cases of a continuum from zero (sympatric) to complete (allopatric) spatial segregation of diverging groups.[3]
In multicellular eukaryotic organisms, sympatric speciation is a plausible process that is known to occur, but the frequency with which it occurs is not known.[4] In bacteria, however, the analogous process (defined as "the origin of new bacterial species that occupy definable ecological niches") might be more common because bacteria are less constrained by the homogenizing effects of sexual reproduction and are prone to comparatively dramatic and rapid genetic change through horizontal gene transfer.