Homologous traits are similar characteristics in different organisms that arise from a common ancestor despite possibly differing functions and appearances. Cladistics is a method that traces evolutionary relationships using homologies, while the paleo species concept poses challenges due to difficulties in observing reproductive isolation in fossils. The document discusses the complexities of speciation, fossil evidence, and the significance of generalized ancestors in evolutionary flexibility.

1. What are homologous traits? Similar traits in different organisms based on common function.
Traits only found in the genus Homo. i.e. living humans and their extinct ancestors. Similar traits
resulting from independent evolution in different groups of organisms. Similar traits in different
organisms based on common descent. How does cladistics differ from evolutionary systematic?
Only cladistics traces evolutionary relationships and constructs classification that reflect these
relationships. Only evolutionary systematics recognizes that organisms must be compared using
specific characters. Only cladistics rigorously defines the kinds of homologies that yield the most
useful information. Only cladistics uses homologous traits to trace evolutionary relationships.
Why is the paleo species concept more difficult to apply to organisms than the biological and the
ecological species concepts? Because reproductive isolation cannot be stuffed directly. Because
ecological distinctions are difficult to impossible in past environments. Because neither exclusive
mating nor ecological niche separation are usually accessible in fossil specimens. Because
homologous traits are rarely expressed in fossil specimens. speciation is characterized by?
Complete reproductive isolation of two populations. Partial reproductive isolation of two
populations. No reproductive isolation of two populations. Complete ecologic niche separation
of two species. What is the age of the oldest known fossils found on Earth: 3.8 billion years. 3.5
billion years. 2 billion years. 520 million years. is the study of: What happens to organic matter
after death. How bones mineralize during fossilization. The rules of classification. Ancestral
traits in closely related species. When general and specialized traits of organisms are considered
in evolution it is important to recognize that only a generalized ancestor can profit from the
flexible evolutionary basis for rapid diversification. Which of the following animals is an
appropriate example for a highly specialized placental mammal that is structurally adapted to a
narrow, rodent/woodpecker-like corniche: The duck billed platypus. The wallaby. The white-
tailed deer. The aye-aye of Madagascar.
Solution
38 d.
Homologous traits are are shared by different species that share a common ancestor. Similar in
structure or genetics, but may have very different functions and appearances. Example: bones in
the wing of a bird and the hand of a primate are homologous