macroevolution (mylab and mastering)

Select the correct statement about phylogenetic trees.

Phylogenetic trees may expand quickly to maximum width and then narrow over time.

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648-Introduction.jpg Which branch point represents the most recent common ancestor of all bears?

branch point 1

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648-Introduction.jpg Which branch point represents the most recent common ancestor of the sloth bear and the spectacled bear?

branch point 2

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648-Introduction.jpg Which branch point represents the most recent common ancestor of the Asian black bear and the brown bear?

branch point 4

To apply parsimony to constructing a phylogenetic tree,

choose the tree that represents the fewest evolutionary changes, in either DNA sequences or morphology.

How does genetic information−−along with an understanding of the process of descent with modification−−enable scientists to reconstruct phylogenies that extend hundreds of millions of years back in time?

All organisms are composed of cells and have their genetic information encoded in DNA. . Daughter species share many similarities with their common ancestor. As a result, all organisms contain both morphological evidence (for instance, cell structure) and genetic evidence of their evolutionary history. Organisms with similar morphologies or DNA sequences are likely to be more closely related than organisms with very different structures and genetic sequences. Untangling evolutionary history from these data requires that characters must be distinguished: homology (similarity because of shared ancestry) from analogy (similarity because of convergent evolution) and shared derived characters (unique to clade) from shared ancestral characters (originated in an ancestor).

https://session.masteringbiology.com/problemAsset/1311559/8/Chap26_Q3.jpg This figure shows a phylogenetic tree of birds and their close relatives. Identify the monophyletic taxon.

Birds and dinosaurs and their common ancestor

Use the same diagram to determine whether each statement is true or false. https://session.masteringbiology.com/problemAsset/2581212/12/ReeceCampbell_VF_PhylogenicRelationships_artbased_PartC.jpg

Branch point 2 is the common ancestor shared uniquely by Taxa A, B, and C. False Rotating the tree at branch point 2 would change the relationship between Taxa D and A. False Branch point 1 represents the common ancestor of Taxa A-F. True Taxa D and E arose from a common ancestor and are sister taxa. True

Suppose that a phylogenetic tree were constructed using the data shown in this table. Mosses represent the outgroup.

Cherries and peas are each other's closest relatives.

How might early members of the manatee lineage have differed from today's manatees?

It is likely that early members of the evolutionary lineage leading to manatees had four legs. Submit

Which of these are homologous structures?

Ivy leaf and pine needle

The branching pattern of a phylogenetic tree indicates whether taxa are closely or distantly related relative to other taxa in the tree. Use this phylogenetic tree to determine whether each statement is true or false.

In this tree, lizards are the sister taxon of the lineage that includes humans and chimps. True The taxon that shares the most recent common ancestor with frogs is fishes. False Frogs and humans are more distantly related than are lizards and humans. True Fishes and chimps have no common ancestors. False

Based on the tree below, which statement is correct? https://session.masteringbiology.com/problemAsset/3056310/5/ch26_q5.jpg

Salamanders are a sister group to the group containing lizards, goats, and humans.

Based on the character table in Part B, which of the following statements about shared derived characters in plants is correct?

Seeds are a shared derived character of pines, cherries, and peas.

Why are manatees considered tetrapods even though they lack hind limbs?

Since manatees are mammals, they also descended from the tetrapod common ancestor. Hence manatees are considered tetrapods.

https://session.masteringbiology.com/problemAsset/2581212/12/ReeceCampbell_VF_PhylogenicRelationships_artbased_PartC.jpg

Taxon A is the sister taxon of the lineage that includes Taxa B and C.

The evolutionary history of a group of organisms can be represented in a branching diagram called a phylogenetic tree. Phylogenetic trees are visual representations of evolutionary relationships between organisms.

The horizontal line indicating a branch on a phylogenetic tree represents ancestral forms of the named taxon, thereby illustrating the evolutionary lineage leading to that taxon. Sister taxa are groups of organisms that share a unique common ancestor not shared by any other groups. The point at which two or more lineages diverge from their common ancestor is called a(n) branch point or node. Each branch tip on a phylogenetic tree represents a specific group of organisms known as a(n) taxon.

https://session.masteringbiology.com/problemAsset/1311536/6/Chap26_Q5.jpg This phylogenetic tree was constructed by comparing sequences for a homologous gene involved in development. Select the correct statement.

The nucleotide sequence of this gene in a mouse is more similar to the sequence in a chicken, and both are less similar to the nucleotide sequence of this gene in a frog.

Look at this character table. Rattlesnakes (like turtles) are reptiles, yet they do not have four limbs. In fact, they have no apparent limbs.

The presence or absence of four limbs, on its own, could be misleading when considering the evolutionary relationships of rattlesnakes.

https://media.pearsoncmg.com/bc/bc_masteringbio/videotutor/05_phylogenetictrees/VT05_Q1_EB4_FIG_14_24.jpg?41&D

The species that is a common ancestor to all species shown on the tree 2 birds time lizards and snakes

Phylogeny is the evolutionary history of related groups of organisms. Organisms are grouped into taxa based on homologous characteristics, shared traits that result from common ancestry. Which statement is true?

The term "monophyletic" refers to a taxon that includes an ancestral species and all of its descendants.

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648-Introduction.jpg The tree includes the most recent common ancestor of all living species of bears (branch point 1). What does this tell you about this phylogenetic tree?

This phylogenetic tree is rooted.

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648_I_1.jpg Based on the revised branch of the tree, what kind of group do brown bears plus ancestral species 7 represent?

a paraphyletic group

Three living species X, Y, and Z share a common ancestor T, as do extinct species U and V. A grouping that consists of species T, X, Y, and Z (but not U or V) makes up

a paraphyletic group.

In a comparison of birds and mammals, the condition of having four limbs is

a shared ancestral character.

Animals that possess homologous structures probably __________.

evolved from the same ancestor

Choose traits that manatees likely share with leopards and other mammals.

hinged jaws vertebral column hair amnion

Imagine that you are studying alien life-forms discovered on a distant planet. While geneticists are working out the genetic code of these organisms, you are asked to construct a phylogenetic tree based on four morphological features, or characters: presence or absence of a spring tail, presence or absence of a grasping hand, presence or absence of a second tail, and number of eyes. The organisms have been divided into five groups based on these characters.

https://media.cheggcdn.com/study/21f/21feaa62-53c7-44bc-bcae-f926dc4b0f9a/281f645e-7055-401c-ae15-9fb3608d8b4e.png a. spring tail b. fourth eye c. second tail d. grasping hand e. tail stalk, 3 eyes f. spring tail, 3 eyes g. spring tail, 4 eyes h. 2 spring tails, 4 eyes i. spring tail, spring tail with grasping hand, 4 eyes

The geneticists studying the alien organisms have deciphered their genetic code. For familiarity, they have used A, C, G, and T to indicate the bases in this code. A comparable genetic sequence in each alien has been identified in the genes that code for eye growth. This genetic sequence has allowed the aliens to be divided into six groups, with the single-tail, three-eye group split in half. The geneticists also studied several outgroup species (not shown) to compile a likely ancestral DNA sequence. From this information, they have constructed four possible phylogenetic trees. Based on this genetic information, which phylogenetic tree is most parsimonious?

https://session.masteringbiology.com/problemAsset/1099036/38/1099036_016.jpg

A study published in 2000 sequenced part of the mitochondrial cytochrome b gene from 61 brown bears from two sites in Alaska. One population of brown bears lives on the coastal mainland of Alaska, while a separate population lives on the ABC islands in southeastern Alaska. Mainland and ABC brown bears differ by 11 fixed nucleotide substitutions in the cytochrome b gene. This suggests that the two brown bear populations represent genetically unique clades. The researchers compared the cytochrome b sequences of the two clades of Alaskan brown bears to those of 55 polar bears. The analysis showed that polar bears and ABC brown bears differ at only three nucleotides in this gene, whereas polar bears and mainland brown bears had more differences. Based on the results of the 2000 study, how should the portion of the tree extending from branch point 7 be altered?

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648_I_1.jpg

Turtles are not shown on this tree. Turtles are evolutionarily more closely related to lizards than they are to frogs.

https://session.masteringbiology.com/problemAsset/2581212/12/ReeceCampbell_VF_PhylogenicRelationships_artbased_PartE_1.jpg

By definition, a clade is __________.

monophyletic

Systematists have used a wide variety of traits (characters) to reconstruct the phylogenies of particular groups of organisms. Which of the following types of characters are used to estimate a phylogeny?

morphological characters and DNA sequence characters

This is one possible phylogenetic tree representing the relationships between some members of phylum Arthropoda. Use this phylogenetic tree and your knowledge of cladistics to determine the relationships between these species.

most closely related to horseflies flea katydid human body louse mayfly dragonfly silverfish

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648-Introduction.jpg Which of the following groups of species is a monophyletic group, or clade?

sun bear, Asian black bear, American black bear, ancestral species 5, ancestral species 6

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648-Introduction.jpg Identify the sister taxon to the polar bear.

the brown bear

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648-Introduction.jpg Which species is the basal taxon in this tree?

the giant panda

https://session.masteringbiology.com/problemAsset/1509648/15/MB_1509648-Introduction.jpg According to this tree, is the sun bear more closely related to the sloth bear or the polar bear?

the polar bear

Use the figure to answer the following question. Gymnosperms and angiosperms are both types of plants that produce seeds. https://session.masteringbiology.com/problemAsset/3074964/4/26.1-35.jpg

the tree depicts an evolutionary hypothesis