Traditionally, Zoologists Have Placed Birds in Their Own Class, Aves

question 40

Multiple Choice

Traditionally, zoologists have placed birds in their own class, Aves. More recently, molecular evidence has shown that birds are more closely related to reptiles than their anatomy reveals. Genetically, birds are more closely related to crocodiles than crocodiles are to turtles. Thus, bird anatomy has become highly modified as they have adapted to flight, without their genes having undergone nearly as much change.
-Traditional zoologists have long agreed that birds evolved from dinosaurs. What keeps such zoologists from agreeing that birds, like dinosaurs, should be considered reptiles?

• A) There is not yet enough evidence to be sure.
• B) Stubbornness, insofar as they are unwilling to change their thinking when new data warrants it.
• C) They deny the validity of genetic molecular data.
• D) They differ in what they consider to be important traits for assigning organisms to the class Reptilia.

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Definitions:

Demand Curve

A graphical representation showing the relationship between the price of a good or service and the quantity demanded.

Equilibrium Price

The price at which the quantity of a product offered is equal to the quantity of the product in demand, thus the market is in balance.

Compact Discs

Optical storage media used to store data, including music and software, readable by laser-based players and computers.

Demand

The quantity of a good or service that consumers are willing and able to purchase at various prices during a certain period of time.