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To say that species A is more closely related to species B than to species C is to say that A and B
a. have a more ancient common ancestor than do A and C.
b. have a more recent common ancestor than do A and C.
c. are more similar in appearance than are A and C.
d. live in the same area, but C does not live there.
Introduction:
The evolutionary tree is constructed based on the anatomical and molecular similarities among different organisms. When two species A and B diverged from a common ancestor the similarities of traits found in the two species can be present in the more recent common ancestor. When species C does not share traits or the genetic differences are high compared to species A and B than species C is not descendant of an ancestor of A and B.
Answer to Problem 1MC
Correct answer:
The species A is more closely related to species B, it means that species A and B have a more recent common ancestor than do A and C.
Explanation of Solution
Explanation for the correct answer:
Option (b) is given that species B and A are more closely related as they have a more recent common ancestor as compared to A and C. The species B and A diverged from a more recent common ancestor due to mutations. Thus, the genetic differences between A and B are less than those between A and C when three species are compared. This implies that A and B are closely related. Hence, option (b) is correct.
Explanation for incorrect answers:
Option (a) is given that species B and A are more closely related as species B and A have a more ancient common ancestor than do A and C. The descendants of the most recent ancestor are said to be more closely related, whereas the descendants of more ancient common ancestors are less closely related. So, it is an incorrect option.
Option (c) is given that species B and A are more closely related as they are more similar in appearance than are A and C. The similarities in appearance are not used to compare closely related species. It is the molecular similarity determined by analyzing the genetic level, which is the key to find the divergence from a common ancestor. So, it is an incorrect option.
Option (d) is given that species B and A are more closely related as they both live in the same area but C does not live there. The place of living is not considered to find the close relationship between the species, as it is the genetic similarities, which determine whether the species are closely related or not. So, it is an incorrect option.
Hence, options, (a), (c), and (d) are incorrect.
Thus, it can be concluded that the species B and A are more closely related as they are descendants of a more recent common ancestor. The close relation is determined using molecular analysis.
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Chapter 19 Solutions
BIOLOGY: LIFE ON EARTH-W/MASTERING ACCE
- Consider the cladograms below Which species is extinct in both cladograms? In which cladogram are species B & C most closely related? Question 6 options: C; the one on the left E; The one on the right E; There is no way to tell/insufficient information is provided B; the one on the leftarrow_forwardParaphyletic groups... A. represent the most recent common ancestor and all of the descendants B. Are a potential consequence of secondary loss of a trait C. Are often created when attempting to build phylogenies for species that have undergone convergent evolution D. Are more likely when making trees using the biological species conceptarrow_forwardWhich condition is the basis for a species to be reproductively isolated from other members? a. It does not share its habitat with related species. b. It does not exist out of a single habitat. c. It does not exchange genetic information with other species. d. It does not undergo evolutionary changes for a significant period of time.arrow_forward
- Below is a phylogenetic tree. Which of the following statements is correct? Species C and D are called sibling taxa because both are derived from the same parent species H. Species F is more related to species K than species D is. Species A, B, and D share a common ancestor of species I. All species shown are currently with us. All of the abovearrow_forwardWhat is not always true of a valid binomial species name like Homo sapiens? A. It includes the genus name B. It is the first published name applied to the biological species C. It is defined by autapomorphic character states D. Technically, it consists of a noun and an adjective asaparrow_forwardWhich of the following is not part of how we define a species? a. Its individuals appear different from other species. b. It is reproductively isolated from other species. c. Its populations can interbreed. d. Fertile offspring are produced.arrow_forward
- One problem with the morphological species concept is that… Group of answer choices A. organisms that appear identical can be reproductively isolated B. can’t be applied to species that don’t evolve C, it is very confusing D. it can’t be applied to organisms without sexual reproduction E. elopment has nothing to do with speciationarrow_forwardA study of two populations of similar organisms determined that the two populations were different species using the phylogenetic species concept. Is it possible for the two populations to also be defined as two different species using the biological species concept? Explain your answer.arrow_forwardWhat is the phylogenetic definition of a species? A) A group of individuals that can breed and produce viable offspring B) A group of interbreeding individuals that share the same environment C) A group of individuals that share a common ancestorarrow_forward
- What is a species, according to the biological species concept? Using at least 3 examples, please explain why this definition is not always practical for all species.arrow_forwardA paraphyletic group includes a. an ancestor and all of its descendants. b. an ancestor and some of its descendants. c. descendants of more than one common ancestor. d. All of the choices are correct.arrow_forwardIn the figure below, each number represents a species. The closer two numbers are on the diagram the more similar the two species. The circles represent taxonomic groups. For example, the diagram shows that 2, 3, 4, and 5 are in the same genus. (Species within a group may be written as 2-5, 11-16 etc. Separate two or more groups with a coma) A. State one species that is in a genus with no other species B. State the species that are in a family with 2 genera C. State the species that are in order with 2 families D. State the species that are in a class with 3 orders E. Deduce whether species 8 is more closely related to species 16 or species 6 F. Explain why three concentric circles have been drawn around species 34 on the diagramarrow_forward
