Exam 18: The Outcomes of Evolution: Macroevolution

In an organism's binomial scientific name,the first of the two names is the

________ isolating mechanisms are outside factors that prevent interbreeding.

Two different species of pines release their pollen at different times.This is an example of:

There are currently many similar but different species on either side of the isthmus of Panama.They probably resulted from:

Which field of biology is concerned with the diversity and relatedness of organisms?

Two species of garter snakes live in the same geographic area.One mainly lives in water,and the other mainly on land,so they rarely encounter each other and do not interbreed.This is an example of what type of isolating mechanism?

Horses and donkeys mate successfully to produce mules,which are always sterile.Which genetic isolating mechanism is involved here to prevent horses and donkeys from becoming a single species?

Which of these is not gametic isolation?

Speciation can never occur unless populations become separated by a geographic barrier.

In the early nineteenth century,the French scientist Georges Cuvier provided conclusive evidence of the extinction of species on Earth.Although Cuvier correctly asserted that a series of catastrophes led to these extinctions,he could not provide a testable explanation of the source of the new animals and plants that appeared after the extinction of older forms.How would you argue that modern evolutionary theory provides an explanation for the proliferation of new forms of life after mass extinctions?

Which of these definitions of species most closely fits the biological species concept?

Species A is divided by a newly formed river to become two populations.These populations diverge to become two different species,B and C.If the river is dammed upstream,eliminating an isolating mechanism between B and C,what will happen?

Speciation can occur without dramatic anatomical or genetic change.

Blue-footed boobies of the Galapagos will mate only after a very specific courtship display on the part of the male.He high-steps to advertise his bright blue feet.What isolating mechanism discourages mating outside the species?

About 50,000 animal species are vertebrates,yet only some vertebrates then went on to evolve four limbs.This tetrapod feature is considered to be a/an ________ of vertebrates.

Describe the difference between homologous and analogous structures in organisms,and give an example of each.

A population of mountain-dwelling salamanders migrates and splits into two populations separated by a valley they can not cross.The speciation process that may occur is:

The biological species concept is based on:

The biological species concept cannot be applied to bacteria because:

Thinking of the examples in your book of adaptive radiation,in which of the following environments might you be most likely to find adaptive radiation?