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Flashcards in Chapter 4 Deck (32):
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Charles Darwin

Inferred the patterns of common ancestry with out a mechanistic understanding of genes and hereditary; developed a hypothesis about past events that later became testable; argued that humans descended from another primate species

1

Linnaean taxonomy and the resulting system of scientific nomenclature

was derived from evolutionary thinking*; has been used by biologists for nearly 3 centuries

*double check the first part on ppt

2

Carolus Linnaeus (1707-1778)

Was a Swedish botanist, zoologist and physician; wrote Systema Naturae; had the insight that organisms can be organized into a system hierarchical classification without having a theoretical explanation for why these patterns should exist

3

German biologist Willi Hennig (1913-1976)

Established the modern approach to classification; documented evolutionary history in his book Phylogenetic Sytematics; notes that phylogenetic trees can help us to classify organisms according to their evolutionary history

4

The study of phylogeny predominantly aims to

understand the branching relationships of populations as they give rise to descendant populations over time

5

The study of phylogeny allows us to understand the

major events in evolutionary history; history of descent; relationships among taxa of organisms

6

The study of phylogeny rests on our observation of traits, which may include

anatomical features; embryological processes; genetics sequences

7

Which of the following statements about pedigrees and phylogenies is true?

A pedigree tells us about the ancestry of individuals, whereas most phylogenies tell us about the ancestry of populations

8

Traits are critical in the study of phylogeny because

We use observations of traits to infer patterns of ancestry and descent among populations;
By mapping individual traits onto a phylogeny we have already created, we can study the sequence and timing of evolutionary events

9

A trait that is similar in one or more species even though it was not present in their common ancestor is called a

homoplasy

10

Although they serve no current functions, vestigial traits persists in some organisms because

the trait is not costly to the organism; natural selection does not act against the trait; there is some NS against the trait, and it is on its way out- eventually will be lost

11

Which of the following terms is used for a situation in which the derived trait has arisen recently and appears in only one of the two most related species or populations, while the two most distantly related groups share the same trait?

SYMPLESIOMORPHY

12

Suppose a population of traits splits into two descendant populations prior to the evolution of dark coloration, then splits again after the evolution of dark coloration. Which of the following terms best describes the dark coloration trait in this situation?

Synapomorphy

13

Convergent evolution occurs when

Two or more populations or species become more similar to each other because they are exposed to similar selective conditions

14

Divergent evolutions occurs when

Closely related populations or species diverge from one another because natural selection operates differently on each of them

15

Analogous traits are found in two or more species because

some evolutionary process (usually NS) has independently fashioned similar traits in each species

16

Homologous traits are found in two or more species because

those traits are from a common ancestor

17

By placing a given trait on a phylogenetic tree that we have already constructed using other data, we can

generate a hypothesis about when and how this trait evolved

18

cladogram

a tree with aligned branch tips that indicated only the evolutionary relationships among the taxa shown

19

Phylograms

A tree in which branch lengths represent the relative AMOUNT of evolutionary change

20

Chronograms

A tree in which branch lengths represent actual TIME rather than the amount of evolutionary change

21

Based on the figure of flower color and morphology (shape), which of the following statements are true?

NONE:
-flower shape was used to infer this phylogenetic tree
-the origin of a new flower shape evolved after the origin of dark color
-the origin of a new flower shape evolved before the origin of dark color

22

Based on the phylogenetic tree above, which of the following groups is most closely related to mammals?

All reptiles and birds

23

Based on the figure above on genetic sequence data, which of the following statements is true?

There is a one base change between the analyzed sequences of lineages 1 and 2

24

Based on the two phylogenetic trees (with time) figure, which statement is true?

The two phylogenies of the vertebrae shown illustrate exactly the same information

25

Based on the two phylogenetic trees (with time) figure, which of the following two groups are most closely related?

Birds and crocodilians

26

Based on the two phylogenetic trees (with time) figure, the two roots (labeled) represent which of the following?

1. Ancestral populations
2. A common ancestor of birds and crocodilians
3. A common ancestor to all tetrapods
4. The ancestral lineage from which all other lineages on the tree are derived

27

Based on the two phylogenetic trees (with time) figure, what does the upper dot in each figure represent?

An ancestral population; the most recent common ancestor to all tetrapods

28

Based on the two phylogenetic trees (with time) figure, what does the INTERIOR dot in each figure represent?

An ancestral population; common ancestor of birds and crocs

29

Based on the two phylogenetic trees (with time) figure, which is true?

Fish is not a monophyletic group; Tetrapod vertebrates is a monophyletic group

30

Vestigial traits serve as a strong test of Darwin's theory of evolution by common ancestry. Based on the figure, which limbless organisms would you expect to find vestigial limbs?

Snakes

31

Based on the figure (shrublike or treelike species circled in black), which of the following is true?

For the herbaceous species, the branch lengths tend to be longer, and the rates of sequence change faster