Question

Consider 37 species of poison dart frogs that live in Central and South America. They use either of two different poison compounds, poison "A" or poison "B".

You are working in a lab that is studying these poisons, and you've been asked to work on the problem of "How did these poisons evolve", or put another way, "Why do some frogs use "A" and some use "B"?

You come up with two ideas that you think are plausible.

H1: The frogs get the poison from their diet, and their diet determines which poison they can make.

H2: The frogs synthesize the poisons themselves; One poison evolved first, and the other poison is a variant of the original (due to a slight modification in the pathway that leads to the poison).

Choose which kinds of data you would need to collect to test your two hypotheses.

The nucleotide sequences from a the same region of non-coding DNA for each species

The weight of each species

The average number of offspring each species has

The geographic range of each species

A list of which species use which toxin

A list of what all species of frogs in the area eat, whether they are poison dart frogs or not.

The color and/or pattern of each species

Answer 1

• The nucleotide sequences from a the same region of non-coding DNA for each species - Analyzing the non-coding sequences can help in determining whether the two species compared are related and the integrity of the genome is protected. But analyzing the genes coding for the toxins will be much more helpful.
• The geographic range of each species - Analyzing the geographic range of each species helps in determining the diet, the environmental conditions and predators that may have influenced the nature of the toxins.
• A list of which species use which toxin - The type of toxin used by the species will be helpful in organizing the study.
• A list of what all species of frogs in the area eat, whether they are poison dart frogs or not - will be helpful in determining whether the diet is the source of poison.