Evolutionary Relationships By Ashton

Consider the phylogenetic tree of Old World primates. mc012-1.jpg According to the tree, which primates share the most recent common ancestor with humans?

Which describes the modern classification system?

Protists are a group of organisms that are characterized as eukaryotes (they have cells with nuclei) that are neither plants nor animals nor fungi. They are very diverse, and there are many hypotheses about their classification. The cladogram for protists is constantly changing and, sometimes, there are opposite hypotheses that both have data to support them. What is the implication of a changing hypothesis?

Which best describes derived characteristics?

According to the cladogram, which organisms are in the smallest clade with birds? mc011-1.jpg

Dr. Digger, a paleontologist, finds a fossil that he describes in his journal. The creature was approximately 1 meter long, with its backbone fused into a large shell covering the body cavity. It had a beaklike mouth, without teeth, and all four limbs were in the form of flippers. Based on anatomical similarities, to which modern animal is Dr. Digger's creature most closely related?

If two organisms are in the same clade, what can you predict about their relationship?

Consider the cladogram. mc014-1.jpg Which group of organisms has the derived characteristics of true tissues, bilateral symmetry, and a pseudocoelom?

In a cladogram, what occurs at a node?

Julia is trying to place a duckbilled platypus, lizard, bear, and monkey on a phylogenetic tree. She learns that the duckbilled playpus, bear, and monkey are classified as mammals. She also learns that mammals share a common ancestor with reptiles. Which additional piece of information will be most helpful to Julia to properly build her phylogenetic tree?