Life Over Time and Mass Extinctions Flashcards Preview

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Flashcards in Life Over Time and Mass Extinctions Deck (44)
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1
Q

Why are plants and animals in India different than Southeast Asia?

A

India was its own continent until 45 million years ago

2
Q

Angiosperm

A

flowering plant

3
Q

Gondwana

A

Ancient supercontinent that consists of Africa, South America, Australia, Antartica, India, and the Arabian Peninsula

4
Q

How do lizard species on mainland California compare in diversity to those found on islands?

A

Due to greater ecological opportunities on islands, there is greater differences between island species

5
Q

What is exceptional about the early animal faunas from the Ediacaran period just before the Cambrian?

A

soft-bodied animals are well represented by these fossils

soft bodied fossils are rare

6
Q

Key innovation (evolutionary innovation)

A

a novel phenotypic trait that allows subsequent success of a taxonomic group

7
Q

Does genetic drift directly cause adaptive radiation?

A

No

8
Q

Can an unusual event splitting a habitat, such as a hurricane led to adaptive radiation?

A

No

9
Q

When did Pangea occur?

A

Late Paleozoic and early Mesozoic era

10
Q

What major evolutionary episode corresponded the closest with the formation of Pangea?

A

Permian extinctions

11
Q

How do fossils start to form?

A

Start with burial in sediment

12
Q

Intact fossil

A

forms when decomposition does not occur and the organic remains are preserved intact

13
Q

Compression fossil

A

forms when sediments accumulate on top of the organism and become cemented into rocks such as mudstone or shale

the sediments weight compresses the organic material below into a thin, carbonaceous film

14
Q

Cast fossil

A

forms when organisms decompose after they are buried

the hole that remains fills with dissolved minerals, which creates an accurate cast of the remains

15
Q

Permineralized fossil

A

forms when organisms decompose extremely slowly

16
Q

Trace fossil

A

forms when sedimentation and mineralization preserve indirect evidence of an organism in the environment

ex: footprints, tracks, feces

17
Q

Conditions for fossils to occur

A
  1. buried rapidly

2. decompose slowly

18
Q

Habitat bias

A

Organisms that live in areas where sediments are actively being depositing (beaches, swamps) are much more likely to form fossils than are organisms that live in other habitats

19
Q

Taxonomic and Tissue Bias

A

Organisms with hard parts, such as bones or shells, are most likely to leave fossil evidence

similar idea applies with tissues

20
Q

Temporal bias

A

Recent fossils are much more common than ancient fossils

The older a fossil is, the longer it has been exposed to destructive forces

21
Q

Abundance bias

A

fossil record is weighted towards common species

22
Q

Paleontologists

A

scientists who study fossils

23
Q

Why is it hard to estimate when species first appeared in the fossil record?

A

A particular species or lineage can exist for millions of years before leaving fossil evidence

24
Q

Precambrian

A

Interval between the formation of the earth and the appearance of most animals (541 bya)

Unicellular

Oxygen was virtually absent until photosynthetic bacteria

25
Q

Phanerozoic Eon Eras

A

Paleozoic, Mesozoic, and Cenozoic

26
Q

Paleozoic Era

A

starts with appearance of most major animal lineages

ends with the obliteration of almost all multicellular life-forms (end-permian extinction)

initial diversification of the animals, land plants, and fungi, as well as the appearance of land animals

27
Q

Mesozoic Era

A

begins with end-permian extinction and ends with the extinction of the dinosaurs

gymnosperms were dominant plants

dinosaurs were dominant vertebrates

28
Q

Cenozoic Era

A

angiosperms were dominant plants

mammals were dominant vertebrates

29
Q

What era are we currently in?

A

Cenozoic era

30
Q

Adaptive radiation

A

the sudden appearance of related, diverse species in the fossil record

31
Q

3 Hallmarks of Adaptive radiation

A

1) monophyletic group
2) speciated rapidly
3) diversified ecologically (occupy many niches)

32
Q

Niche

A

range of conditions that a species can tolerate and the range of resources that it can use

33
Q

Ecological opportunity

A

Can trigger adaptive radiation

marked by the availability of more resources

34
Q

When did most modern animal phyla evolve?

A

Paleozoic

35
Q

When did animals first appear?

A

Precambrian

36
Q

Flowering plants first appeared during?

A

Mesozoic era

37
Q

How to determine if two species are an example of adaptive radiation?

A

Ask yourself if they came from a single lineage

38
Q

Stromatolites

A

fossilized mats of billions of bacteria cells

oldest found 3.5 bya

39
Q

What era was the Cambrian explosion?

A

Paleozoic

40
Q

What conditions allowed for the Cambrian explosion?

A

1) oxygen levels rose rapidly
2) evolution of predation
3) new niches beget more new niches
4) new genes, new bodies

41
Q

What new genes were developed during the Cambrian explosion?

A

Hox genes

determine where things are placed in the body developmentally

42
Q

3 domains of life

A

Bacteria, archaea, eucarya

43
Q

Intrinsic factors of adaptive radiation

A

Evolution of key morphological, physiological, or behavioral traits

These traits are called synapamorphies

44
Q

Extrinsic factors of adaptive radiation

A

ex: favorable new conditions in the environment