8) you are studying a group of chameleons that are currently present across many southern hemisphere landmasses. species 1 is found in australia, species 2 in madagascar, species 3 in south america, species 4 in new zealand, species 5 in africa, and species 6 in new guinea. you hypothesize that the current species distribution is due to an ancestral chameleon that inhabited gondwana and was speciated as the continent broke up. draw a phylogeny that is consistent with this hypothesis. (assume that this is the order of breakup: madagascar – 160 mya, africa – 100 mya, new zealand – 85 mya, australia and new guinea 60 mya, and finally south america and antarctica split 35mya). it turns out that most of the distribution is due to vicariance, but species 2 (madagascar) dispersed from africa, and species 4 (new zealand) dispersed from australia after the australia and new guinea lineages split. draw a phylogeny consistent with this hypothesis.

Explanation:

Dispersion and vicariance are the processes by which speciation is generated in biogeography.

A phylogeny represents the evolutionary relationships between different species.

In this phylogeny, species 5, 1, 6 and 3 originated from vicariance processes, and their position in the phylogenetic tree is due to the order of separation of the mentioned regions. Species 2 and 4 originated from dispersal processes, and are expected to have a closer evolutionary relationship with the species that were in the areas from which they were dispersed, in this case, with Africa and Australia respectively.

amber has allowed scientists to study dna that has been preserved over millions of years.

the relative standard reduction potential of the half-cell in which reduction occurs; more positive than the other half-cell. reduction is a chemical process in which electrons are added to an atom or an ion; it always occurs accompanied by oxidation of the reducing agent.