Which of the following explains why a bone in a bird’s wing is homologous to a bone in a lizard’s front leg?

a.The bones in the two species provide for the same type of motion.
b.The bones in the two species are both vestigial structures.
c.The two species were exposed to the same environmental pressures.
d.The two species have a common ancestor.
D?

1. D

2. B
3. A
4. C

Yes

I agree.

http://itc.gsw.edu/faculty/bcarter/histgeol/paleo2/homol1.htm

Hal is 100% right thanks so much!

Thanks Hal

Yes, the correct answer is (d) The two species have a common ancestor.

To determine this, you can analyze the concept of homology. Homology refers to similarities in structures that suggest a common ancestry. In this case, the bone in a bird's wing and the bone in a lizard's front leg have similarities indicating a shared evolutionary history.

To arrive at this conclusion, you can also consider the following steps:
1. Identify the bones in question: A bone in a bird's wing and a bone in a lizard's front leg.
2. Analyze the structures and their functions: Compare the bone structures and their respective functions in both species. In this case, birds and lizards both have limbs that play a role in movement.
3. Determine if the bones serve the same purpose: Birds use their wing bones for flying, while lizards use their front leg bones for walking or running.
4. Evaluate if the similarities are due to convergent evolution or shared ancestry: Convergent evolution happens when unrelated species independently evolve similar traits due to adapting to similar environments. However, in this case, the similarity in bone structure suggests a shared ancestry rather than convergent evolution.
5. Consider other factors: Eliminate options like vestigial structures (b) since both species use their respective bones for specific functions. Likewise, environmental pressures (c) may lead to certain adaptations, but they don't explain the similarities in bone structure between birds and lizards.

Therefore, the most appropriate explanation for the homology of the bone in a bird's wing and a bone in a lizard's front leg is that the two species have a common ancestor (d).