Study Guide
(Evolutionary History)
Lesson 1.2
What is the definition of a body structure?
a part of an organism ( for example, one or more bones )
What is the definition of a fossil?
naturally preserved evidence of life
What are ALL the observations paleontologists will use to identify a fossil in order?
1) Pay careful attention to body structures, especially how bones are grouped together
Observe the size of bones within body structures
Observe the position of body structures
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.
What do paleontologists do with the observations they make?
They use observations of fossil evidence to make careful comparisons to other fossils and living species
What is the definition of a limb?
an organism’s arm, leg, or wing
What is the definition of extinct?
having died out completely and no longer alive anywhere on Earth
What is the definition of a species?
a group of organisms of the same kind ( in one or more populations ) that do not reproduce with organisms from any other group
What is the definition of a paleontologist?
a person who studies fossils to understand the history of life on Earth
Lesson 1.3
What is a generation?
a group of individuals born and living at about the same time
What is a common ancestor population?
an older population from which two or more newer species descended
What are body structures determined by?
The code of DNA and how it gets passed down through generations over many years
What is the definition of a shared structure?
When two species' body structures are made from bones that are in the same pattern and have a similar position in the body
What is the definition of a descendent species?
a more recent species that evolved from an ancestor population
What is the definition of evolution?
so many changes that the organism is a different species
What two main types of evidence do Paleontologists use to determine common ancestors?
Fossils and DNA
What is the definition of related?
sharing a common ancestor population
What is the definition of inherit?
to receive genes from a parent
What’s the difference between a species and a population?
A species is one type of organism that doesn’t reproduce with any other species, but a population is a group of the same type of organism living in the same area
Do shared structures always have the same purpose?
No, they don’t. This is because if an organism has the same body structure as another, they might not all use it for the same thing. An example of this would be one organism could use their distal bones for swimming and another for running.
What's the definition of a trait?
A specific characteristic of an individual organism
What did all living things evolve from?
All living things evolved from the same single-celled organism long ago
What is the definition of an ancestor species?
An older population from which a species descended
What is the definition of an organism?
living things, such as plants, animals, and bacteria
How long ago did the first living organism (a single cell) from which every other organism evolved from life?
4 billion years ago
How long ago did the first mammal, from which all other mammals including humans, evolved live?
65 million years ago
If an organism looks similar to another, does that mean they are related? Why or why not?
No, they could not be related if they look similar. This is because they would have to have a similar body structure, meaning they had a common ancestor at some point.
What are body structures determined by?
The code of DNA and how it gets passed down through generations over many years
____shared________ ____body structures__________ in two very different species can be evidence that both species evolved from a common ancestor.
What are two things that all organisms would share (have in common) if they are related to each other?
Cell structure and DNA
Lesson 2.2
What is a mutation?
a random change to a gene that sometimes results in a new trait.
What is speciation?
the process by which one population evolves into two or more different species
What is the definition of stability? Give an example
When something stays mostly the same over time. Over 20 years, the distribution of the species only went down by 3
What is the definition of an environment?
everything biotic and abiotic that surrounds an organism
What is natural selection?
The process by which the distribution of traits in a population changes over many generations
What is an adaptive trait?
trait that makes it more likely that an individual ( organism ) will survive in a specific environment.
Evolution happens as a result of ___speciation___________.
What is the most common way that a population gets separated for speciation to occur?
When a barrier, such as a mountain range or body of water separates a population.
The process of speciation takes place slowly __________ as adaptive mutations build on one another over many ______generations____________.
What is the definition of evolutionary time?
The very long time that spans the history of Earth, from the very first cellular life to the present
How long ago did evolutionary time start?
Roughly 4 billion years ago
Notes from Lectures:
What is a diagnostic structure?
any structure that helps you identify an organism’s place on the evolutionary tree ( small things that help you pinpoint where the organism goes on the evolutionary tree )
Why does a descendent species have structures different from those of its ancestor?
Because environments change over time, the adaptions must change with it. The organism gets the adaptations from either the previous generation/s or develops it over time because it will help it survive in the environment.
Give at least 3 examples of diagnostic structures that can help classify an organismSame nose, same ribcage, same tail
What is the definition of a physical adaptation? Give an example.
Any part of an organism’s biology that helps it survive in its environment. ( ex: the color of its fur, the thickness of its fur )
What is the definition of a behavioral adaptation? Give an example.
An action an organism takes that helps it survive in its environment ( ex: birds migrating, ants in colonies )
Study Guide
(Evolutionary History)
Lesson 1.2
What is the definition of a body structure?
a part of an organism ( for example, one or more bones )
What is the definition of a fossil?
naturally preserved evidence of life
What are ALL the observations paleontologists will use to identify a fossil in order?
1) Pay careful attention to body structures, especially how bones are grouped together
Observe the size of bones within body structures
Observe the position of body structures
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.
What do paleontologists do with the observations they make?
They use observations of fossil evidence to make careful comparisons to other fossils and living species
What is the definition of a limb?
an organism’s arm, leg, or wing
What is the definition of extinct?
having died out completely and no longer alive anywhere on Earth
What is the definition of a species?
a group of organisms of the same kind ( in one or more populations ) that do not reproduce with organisms from any other group
What is the definition of a paleontologist?
a person who studies fossils to understand the history of life on Earth
Lesson 1.3
What is a generation?
a group of individuals born and living at about the same time
What is a common ancestor population?
an older population from which two or more newer species descended
What are body structures determined by?
The code of DNA and how it gets passed down through generations over many years
What is the definition of a shared structure?
When two species' body structures are made from bones that are in the same pattern and have a similar position in the body
What is the definition of a descendent species?
a more recent species that evolved from an ancestor population
What is the definition of evolution?
so many changes that the organism is a different species
What two main types of evidence do Paleontologists use to determine common ancestors?
Fossils and DNA
What is the definition of related?
sharing a common ancestor population
What is the definition of inherit?
to receive genes from a parent
What’s the difference between a species and a population?
A species is one type of organism that doesn’t reproduce with any other species, but a population is a group of the same type of organism living in the same area
Do shared structures always have the same purpose?
No, they don’t. This is because if an organism has the same body structure as another, they might not all use it for the same thing. An example of this would be one organism could use their distal bones for swimming and another for running.
What's the definition of a trait?
A specific characteristic of an individual organism
What did all living things evolve from?
All living things evolved from the same single-celled organism long ago
What is the definition of an ancestor species?
An older population from which a species descended
What is the definition of an organism?
living things, such as plants, animals, and bacteria
How long ago did the first living organism (a single cell) from which every other organism evolved from life?
4 billion years ago
How long ago did the first mammal, from which all other mammals including humans, evolved live?
65 million years ago
If an organism looks similar to another, does that mean they are related? Why or why not?
No, they could not be related if they look similar. This is because they would have to have a similar body structure, meaning they had a common ancestor at some point.
What are body structures determined by?
The code of DNA and how it gets passed down through generations over many years
____shared________ ____body structures__________ in two very different species can be evidence that both species evolved from a common ancestor.
What are two things that all organisms would share (have in common) if they are related to each other?
Cell structure and DNA
Lesson 2.2
What is a mutation?
a random change to a gene that sometimes results in a new trait.
What is speciation?
the process by which one population evolves into two or more different species
What is the definition of stability? Give an example
When something stays mostly the same over time. Over 20 years, the distribution of the species only went down by 3
What is the definition of an environment?
everything biotic and abiotic that surrounds an organism
What is natural selection?
The process by which the distribution of traits in a population changes over many generations
What is an adaptive trait?
trait that makes it more likely that an individual ( organism ) will survive in a specific environment.
Evolution happens as a result of ___speciation___________.
What is the most common way that a population gets separated for speciation to occur?
When a barrier, such as a mountain range or body of water separates a population.
The process of speciation takes place slowly __________ as adaptive mutations build on one another over many ______generations____________.
What is the definition of evolutionary time?
The very long time that spans the history of Earth, from the very first cellular life to the present
How long ago did evolutionary time start?
Roughly 4 billion years ago
Notes from Lectures:
What is a diagnostic structure?
any structure that helps you identify an organism’s place on the evolutionary tree ( small things that help you pinpoint where the organism goes on the evolutionary tree )
Why does a descendent species have structures different from those of its ancestor?
Because environments change over time, the adaptions must change with it. The organism gets the adaptations from either the previous generation/s or develops it over time because it will help it survive in the environment.
Give at least 3 examples of diagnostic structures that can help classify an organismSame nose, same ribcage, same tail
What is the definition of a physical adaptation? Give an example.
Any part of an organism’s biology that helps it survive in its environment. ( ex: the color of its fur, the thickness of its fur )
What is the definition of a behavioral adaptation? Give an example.
An action an organism takes that helps it survive in its environment ( ex: birds migrating, ants in colonies )
