EVOLUTION EXAM STUDYING

Evolution

Change in genetic makeup of a population over time.

Cross breeding

Mating two individuals from different breeds to produce offspring with desirable traits.

Mutations

Changes in the DNA sequence of an organism.

Inbreeding

Breeding among individuals of the same species.

Allele frequency

The amount an allele is found in a population's gene pool.

Selection pressures

Abiotic or biotic pressures that force species to adapt. Examples include need for food, environmental changes, and diseases.

Biotechnology

Use of living organisms, cells, or biological systems to create technology that improves survival and reproductive success.

Genetic Drift

Change to allele frequency in a population due to chance.

Mimicry

An evolutionary adaptation where organisms evolve to resemble each other to gain an advantage.

Directional Selection

When one extreme phenotype is preferred over the average phenotype in a population.

Macroevolution

Large scale evolutionary changes.

Disruptive Selection

When both extremes are preferred over the population average.

Microevolution

Small evolutionary changes that involve changes in allele frequencies.

Stabilizing Selection

When the average phenotype is preferred in the population.

Speciation

The formation of a new species.

Bottleneck

A sudden, extreme change in population size.

Biological Species concept

Species are groups of organisms that are reproductively isolated and can produce fertile offspring.

Founder Effect

When a small part of a population breaks off to form a new population.

Modes of speciation

Species evolve genetically unique features that isolate them from other species.

Biodiversity

The variety of life on Earth.

Mechanisms of Reproductive isolation

Ways that prevent different species from breeding: Prezygotic (including behavioral, gametic, mechanical, geographical, temporal) and postzygotic (including hybrid inviability, hybrid infertility, zygotic mortality).

Genotype

The genetic makeup of an individual.

Prezygotic

Before the formation of a zygote.

Phenotype

The physical presentation of genes.

Behavioral Isolation

Different animals have different courtship behaviors.

Domestication

When humans control breeding to produce desired plants and animals.

Temporal Isolation

Different organisms breed during different seasons.

Ecological Isolation

Similar species occupy separate habitats.

Gametic Isolation

Male gametes may not recognize female gametes from a different species.

Breeding seasons

Specific times in the year when conditions are optimal for reproduction.

Hybrid infertility

A hybrid offspring is born but is infertile.

Zygotic mortality

Mating occurs but the resulting offspring do not survive.

Allopatric Speciation

Formation of new species due to geographic isolation.

Sympatric Speciation

Formation of new species within the same geographic area.

Gradualism

Evolutionary changes occur slowly over time.

Punctuated Equilibrium

Evolutionary changes occur in rapid bursts followed by periods of stability.

Monoculture

Consequences of artificial breeding leading to genetically uniform populations, risking disease impact on survival.

Sexual selection

Traits that influence mate acquisition enhance reproduction.

Population

A group of species living in the same area that can interbreed.

Gene Pool

The complete set of alleles present in a population.

Microevolution

Changes in allele frequencies within a population and species.

Macroevolution

Large-scale evolutionary changes over long periods.

Speciation

Creation of a new species.

Hybrid inviability

A hybrid individual develops but does not survive to maturity.

Divergent evolution

Related species become distinct; homologous features have the same origin but different functions.

Convergent evolution

Unrelated species develop similar traits due to similar environmental conditions.

Coevolution

Species evolve in response to the evolution of another species.

Abiogenesis

Origin of life from non-living matter.

Transitional forms

Fossils that show intermediate characteristics between two species.

e.g. Archaeopteryx fossil – first and most famous transitional species (features of both birds and primitive reptiles – bony jaw with teeth, long bony tail but also feathered wings)

Adaptive radiation

Rapid evolution of species from a common ancestor to fill diverse ecological niches.

Phylogenies

Classification of species based on a range of evidence.

Cladograms

Visual representations of evolutionary relationships.

Cladistics

Method for determining evolutionary relationships based on recently evolved traits.

Derived traits

Traits that evolve due to adaptations.

Synapomorphy

A derived trait shared by two or more organisms that indicates a close relationship.

what are hardy weinberg’s 5 conditions that drive evolution

1. small population size

2. horizontal gene transfer

3. mutations

4. immigration/emigration

5. natural selection

what are the 5 pieces of evidence for evolution

1. fossil record

2. biogeography

3. DNA sequencing

4. comparative anatomy

5. embryology

what are the 6 mechanisms of evolution

1. gene flow

2. genetic drift

3. natural selection

4. sexual selection

5. artificial selection

6. mutations

what are the 3 types of selection

• directional: one extreme is chosen over the average

• disruptive: both extremes are chosen over the average

• stabilizing: the average is preferred

what are the two types of genetic drift

• bottleneck effect

• founder's effect

biological species concept

a species is a group of organisms that can do inbreeding and produce an offspring and are reproductively isolated

lamarck’s 2 theories

1. use and disuse: parts of an organism used more will become stronger while parts used less will become weaker

2. inheritance of acquired characteristics: characteristics obtained during the parents lifetime can be passed down to offspring (NOT TRUE: THINGS LIKE EYESIGHT CANNOT JUST BE INHERITED)

Pros and cons of lamarck’s theories

• explained how species adapted to environment and how they might evolve if the environment changed (cooler climate --> thicker coat --> pass on to offspring --> better adapted)

• FLAWED because although characteristics may be acquired, many features do not change in response to use --> features that change are not normally heritable

which of the following is the best example of a morphological adaptation?

1. cows have evolved a digestive system to break down grass efficiently

2. wolves in cold climates growing thicker fur in winter months

3. a fish developing the ability to live in both salt and freshwater environments

4. a bat learning to echolocate to find food in the dark

5. a frog producing toxins to deter predators

2

what is the ultimate source of genetic variation in a population

mutations

which of the following best describes an organism’s fitness?

1. the organism’s physical strength and ability to defend against predators

2. the number of mates that an organism can attract

3. the ability of an organism to survive for a long time in its environment

4. the ability of an organism to produce offspring that survive and successfully reproduce in the next generation

4

6. A hurricane wipes out most of a lizard population living on a small island. The surviving lizards happen to have mostly green-coloured scales, not because green is better, but simply because of who survived. This is an example of:

a) Gene Flow

b) Bottleneck Effect

c) Sexual Selection

d) Founder Effect

e) Artificial Selection

b

7. The most important requirement for a population to be considered a species is:

a) selective breeding

b) chromosomal mutation

c) geographic isolation

d) reproductive isolation

e) hybridization

d

8. Which of the following is an example of sympatric speciation?

a) A population of squirrels is separated by a mountain range and evolves into two different species over time.

b) A group of lizards on separate islands evolves into distinct species due to geographic isolation.

c) A population of insects living in the same forest splits into two species because some begin to feed and mate exclusively on a new type of plant.

d) A species of deer migrates to a new continent and eventually becomes a new species due to environmental pressures.

e) A species of frogs becomes separated when a river changes course, leading to the evolution of two species.

c

Which of the following is likely to lead to speciation?

a) A population of rabbits in a forest begins to exhibit a wide range of fur colours

b)Two populations of frogs are suddenly separated by a river

c)A population of birds on an island gradually becomes more similar to a population on a nearby island due to similar environments

d) Bacteria exhibit resistance to different antibiotics within their population

e) Both B) and C)

b

10. Which of the following is the BEST example of coevolution?

a) A population of birds evolves longer beaks to access deeper flowers, and the flowers evolve longer tubes to accommodate the birds.

b) A species of fish becomes more resistant to a common parasite over several generations due to natural selection.

c) A predator evolves sharper claws to catch prey more effectively.

d) A species of tree develops thicker bark to protect against herbivores

e) All of the above

a

Which of the following best describes a transitional species?

a) A species that evolves into two different species due to geographic isolation.

b) A species that exhibits traits that are intermediate between two different groups, providing evidence for evolution.

c) A species that is adapted to extreme environmental conditions and evolves rapidly.

d) A species that has not changed over millions of years and is considered a "living fossil."

e) A species that is genetically identical to its ancestor and has not evolved over time.

b

Which of the following would lead to a population remaining constant according to Hardy Weinberg's tenets?

a) natural selection favouring certain traits

b) immigration

c) emigration

d) No migration

e) Mutations

d

Which of the following best describes Lamarck's theory of evolution?

1. Evolution occurs through the inheritance of traits acquired during an organism's lifetime and they are passed down to future generations.

2. ) Evolution is driven by genetic mutations that occur randomly in populations.

3. ) Natural selection leads to the survival of the fittest, causing gradual change in species over time.

4. ) Organisms are immutable.

5. ) All of the above

1

One finds that organisms on islands are different from, but closely related to, similar forms found on the nearest continent. This is taken as evidence that:

a) The islands were originally part of the continent

b) Common environments are inhabited by the same organisms

c) Island forms and mainland forms descended from common ancestors

d) The island forms and mainland forms are converging

e) Island forms and mainland forms share the same gene pool

c

Which of the following statements best explains the relationship between extinction events and periods of evolution?

1. Extinction events halt all evolutionary processes, causing species to remain unchanged for millions of years.

2. Periods of evolution often follow extinction events, as new species rapidly evolve to fill the ecological niches left vacant.

3. Extinction events occur only during periods of rapid evolution and have no impact on biodiversity.

4. Evolution only occurs during times when no extinction events happen, ensuring the survival of all species.

5. Extinction events are irrelevant to evolutionary processes, as they have no effect on the rate of species change.

2

A population of birds has a range of beak sizes, but over time, the average beak size becomes more common as very large and very small beaks are selected against. The population stabilizes with more birds having beaks around the average size. Which of the following does this reflect?

1. Stabilizing selection

2. Directional selection

3. Diversifying selection

4. Sexual selection

5. Artificial selection