Evolutionary History

Question 1

What is the definition of a body structure?

Answer 1

a part of an organism (for example, one or more bones)

Question 2

What is the definition of a fossil?

Answer 2

naturally preserved evidence of life

Question 3

What are ALL the observations paleontologists will use to identify a fossil in order?

Answer 3

1. Pay careful attention to body structures, especially how bones are grouped together
   a. Observe the size (thickness and length) of bones within body structures
   b. Observe the position of body structures
   c. Observe the same fossil evidence several times to see what you’ve missed
2. Count the number of bones
3. Use observations of fossil evidence to make careful comparisons to other fossils and living species

Question 4

What do paleontologists do with the observations they make?

Answer 4

Paleontologists use the observations to try to find common ancestor species and descendants; Make careful comparisons to other fossils and other species.

Question 5

What is the definition of a limb?

Answer 5

an organism’s arm, leg, or wing

Question 6

What is the definition of extinct?

Answer 6

having died out completely and no longer alive anywhere on Earth

Question 7

What is the definition of a species?

Answer 7

a group of organisms of the same kind (in one or more populations) that do not reproduce with organisms from any other group

Question 8

What is the definition of a paleontologist?

Answer 8

a scientist who studies fossils in order to understand the history of life on life on Earth

Question 9

What is a generation?

Answer 9

a group of individuals born and living at about the same time

Question 10

What is a common ancestor population?

Answer 10

an older population from which two or more newer species descended

Question 11

What are body structures determined by?

Answer 11

A code of DNA passed down from generation to generation.

Question 12

What is the definition of a shared structure?

Answer 12

a body structure in two or more species that features the same parts (for example, the same bones)

Question 13

What is the definition of a descendent species?

Answer 13

a more recent species that evolved from an ancestor population

Question 14

What is the definition of evolution?

Answer 14

the process by which species adapt to environmental changes over a very long time

Question 15

What two main types of evidence do Paleontologists use to determine common ancestors?

Answer 15

Fossils and dna

Question 16

What is the definition of related?

Answer 16

sharing a common ancestor population

Question 17

What is the definition of inherit?

Answer 17

to receive genes from a parent

Question 18

What’s the difference between a species and a population?

Answer 18

Species: group of organisms of the same kind (in one or more populations) that do not reproduce with organisms from any other group
Population: a group of the same type of organism living in the same area

Question 19

Do shared structures always have the same purpose?

Answer 19

No

Question 20

What’s the definition of a trait?

Answer 20

a specific characteristic of an individual organism

Question 21

What did all living things evolve from?

Answer 21

All life evolved from a single celled-organism on Earth 4 billion years ago

Question 22

What is the definition of an ancestor species?

Answer 22

An older population from which newer species descended from

Question 23

What is the definition of an organism?

Answer 23

living things such as plants, animals, and bacteria

Question 24

How long ago did the first living organism (a single cell) from which every other organism evolved from life?

Answer 24

4 billion years ago

Question 25

How long ago did the first mammal, from which all other mammals including humans, evolved from live?

Answer 25

65 million years ago

Question 26

If an organism looks similar to another, does that mean they are related? Why or why not?

Answer 26

No, because they may not have had a common ancestor species or lived in the same environment or their structures were made differently

Question 27

What are body structures determined by?

Answer 27

Shared body structures are determined by a code of dna passed on from their parents

Question 28

____________ ______________ in two very different species can be evidence that both species evolved from a common ancestor.

Answer 28

Shared structures

Question 29

What are two things that all organisms would share (have in common) if they are related to each other?

Answer 29

Cell structure, dna

Question 30

What is a mutation?

Answer 30

a random change to a gene that sometimes results in a new trait

Question 31

What is speciation?

Answer 31

the process by which one population evolves into two or more different species

Question 32

What is the definition of stability? Give an example

Answer 32

when something stays mostly the same over time Ex: when 10 organisms die in a population of 5000

Question 33

What is the definition of an environment?

Answer 33

everything (biotic and abiotic) that surrounds an organism

Question 34

What is natural selection?

Answer 34

the process by which the distribution of traits in a population naturally changes over many generations

Question 35

What is an adaptive trait?

Answer 35

a trait that makes it more likely that an individual will survive in a specific environment

Question 36

Evolution happens as a result of ____________ ___________ .

Answer 36

Natural selection

Question 37

What is the most common way that a population gets separated for speciation to occur?

Answer 37

The most common way that a population gets separated for speciation to occur are barriers.

Question 38

The process of speciation takes place _______________ as adaptive mutations build on one another over many __________________ .

Answer 38

slowly, generations

Question 39

What is the definition of evolutionary time?

Answer 39

the very long time that spans the history of Earth, from the very first cellular life to the present

Question 40

How long ago did evolutionary time start?

Answer 40

from the very first cellular life to the present (3.6 billion years)

Question 41

What is a diagnostic structure?

Answer 41

any structure that helps you identify an organism’s place on the evolutionary tree

Question 42

Why does a descendent species have different structures from its ancestor?

Answer 42

Because they got separated into different environments that had different adaptive traits.

Question 43

Give at least 3 examples of diagnostic structures that can help classify an organism.

Answer 43

Backbone pattern, distal bones size and shape, thickness of certain bones

Question 44

What is the definition of a physical adaptation? Give an example.

Answer 44

any part of an organism’s biology that helps them survive in their environment Ex: thick blubber in a cold environment