Question

evidence for evolution: embryonic development
1 which stage of development did you use to help you identify the different species? circle your answer.
early development (first row) mid development (second row) late development (third row)
2 at which stage do the species look most similar? circle your answer.
early development (first row) mid development (second row) late development (third row)
3 the red arrows point to structures found in all of the early embryos. what do you think these structures are?
4 by late development, some species have lost those structures. with this in mind, suggest why studying embryonic development is useful for studying evolutionary relationships (how closely related species are)

Explanation:

1. In the later stages of development, species - specific features become more pronounced, making it easier to identify different species. So the answer to question 1 is Late development.
2. Early in embryonic development, different species often share many similarities due to common ancestry. So the answer to question 2 is Early development.
3. The red - arrowed structures in early embryos are likely gill slits (pharyngeal arches), which are common in the early embryonic stages of many vertebrates.
4. Studying embryonic development is useful for understanding evolutionary relationships because early - stage similarities can indicate common ancestry. Even if structures are lost in later development in some species, the presence of those structures in the embryo suggests a shared evolutionary past.

Answer:

1. Late development
2. Early development
3. Gill slits (pharyngeal arches)
4. Early - stage similarities can indicate common ancestry.