5. It is possible for two different genes to imply different phylogenetic
relationships among a group of species. What are the possible reasons for this?
If there is only one true history of formation of these species, what might we
do in order to determine which (if either) gene accurately portrays that
history? Is it possible for both phylogenetic trees to be accurate even if
there has been only one history of species divergence?
to lineage or allele sorting, it is possible for two different genes to imply
different phylogenetic relationships among a group of species. Alleles can be
randomly determined at a particular gene loci which are passed from an
ancestral species to a descendant species through a technique that does not
demonstrate the process of speciation. This is remarkably achievable in swiftly
radiating species groups. Another instance could be the distinguishing
transmission of alleles at one gene locus, but not at another gene locus
through horizontal gene transfer or hybridization of nuclear DNA. Hybridization
of nuclear DNA and horizontal gene transfer occurs habitually in prokaryotes.
When attempting to determine which
gene accurately portrays that history we might use a technique commonly known
as “mapping”. Mapping is a process that identifies the distance between the
genes and the locus of a gene. It is best to use as many characters as possible
when using the mapping technique. Making use of a small sample size could lead
to misleading evidence, and does not give future researchers much to work with.
Using a large sample size can provide
more data for researchers to work with. Mapping character states allows one to
compare the different states of each gene being studied, and it can assist in tracing
it back to the root of the entire tree.
I believe that it is possible for
both phylogenetic trees to be accurate even if there has been only one history
of species divergence due to the fact that a phylogenetic trees are mostly
hypothesized. A phylogenetic tree is based upon on a hypothesized belief that a
relationship among different species based on evidence stating that species
have emerged from common ancestors. Therefore, if more than one of the gene
trees have evidence to support their belief their phylogenetic tree can appear
to be accurate until proven otherwise.