Question

biology exam
use the diagram below to answer questions 5 - 7.
hominid skulls
australopithecus afarensis
4 - 3 mya
brain volume 430 cm³
homo habilis
2.4 - 1.5 mya
brain volume 700 cm³
homo neanderthalensis
200,000 - 30,000 ya
brain volume 1500 cm³
homo sapiens
200,000 ya - present
brain volume 1300 cm³

1. which of the skulls shown above would have the most characteristics in common with a chimps skull?

________________________

1. which of the species shown above could have lived at the same time? (hint: which species have overlapping timelines?)

________________________
________________________

1. what features of the skull distinguished the homo genus from the australopithecus genus?

________________________
________________________

1. what is the strongest type of evidence to support common ancestry?

________________________

1. what does it mean for organisms to share a common ancestor?

________________________
________________________

Explanation:

• Question 5: Australopithecus afarensis is the earliest hominid shown. Chimps are more closely related to earlier hominids in terms of evolutionary traits. Earlier hominids like Australopithecus afarensis would share more primitive (and thus chimp - like in some aspects, as chimps are also more "primitive" in the hominid - primate context) skull features such as a relatively smaller brain case compared to later Homo species and more pronounced facial prognathism.
• Question 6: Homo neanderthalensis (200,000 - 30,000 ya) and Homo sapiens (200,000 ya - present) have overlapping time ranges (200,000 - 30,000 ya).
• Question 7: The Homo genus has a larger brain volume (e.g., Homo habilis has a brain volume of \(700\ cm^{3}\) compared to Australopithecus afarensis' \(430\ cm^{3}\)). Also, the Homo genus generally has a less prognathic (less forward - jutting) face.
• Question 8: Genetic evidence is the strongest. DNA sequences can show detailed similarities and differences. For example, the more similar the DNA sequences between two organisms, the more recently they likely shared a common ancestor.
• Question 9: Organisms that share a common ancestor have evolved from a single ancestral species. This means they have inherited genetic material (and often anatomical, physiological, and behavioral traits) from that common ancestor. Over time, due to evolutionary forces like natural selection, genetic drift, and mutation, they have diverged into different species, but still retain some similarities that can be traced back to the common ancestor.

Answer:

1. Australopithecus afarensis
2. Homo neanderthalensis and Homo sapiens
3. Larger brain volume and less prognathic face
4. Genetic evidence
5. Organisms that share a common ancestor have evolved from a single ancestral species, inheriting genetic and often other traits from it.