Grade 11 Biology Evolution test review

Microevolution

- Changes that occur within a species

- natural Selection

-Individuals with advantageous traits pass them on

EXAMPLES: rabbits getting faster, giraffes necks getting longer

Macroevolution

Multiple small changes add up to create large changes over a long period of time

Changes become so drastic that the new population doesn't resemble the old population

Speciation occurs

EXAMPLE: dolphins adapting to have fins and live in water after living on land

Natural Selection

How organisms with traits better suited for their envionment will survive and reproduce, passing their advantageous traits to the next generation

Examples of natural selection are how rabbits evolved to be faster, how giraffes necks grew longer, and how mountain goat's hooves changed to adapt to its environment

Artificial Selection

Artificial selection is when humans select which traits are advantageous and which ones can go into the next generation. The next generation will have more of the traits humans want to be passed on.

Examples of this are how humans created many dog breeds, and how cabbage and broccoli were made.

Fitness

A measure of an organisms survival and reproductive success in an environment

Survival of the fittest

An individual that fits in the most with its environment will survive

Adaptation

A trait shaped by natural selection that increases an organism's survival or reproductive success

Example: camoflauge, mimicry

Selection Pressures

Factors in an organism's environment that affect its chances of survival and reproduction

Competition

An interaction between species and organisms that require the same limited resources like water, food, shelter, and mates

Random mutation

As a cell copies its DNA before dividing, random mutations can occur. These mutations can be passed to offspring and cause genetic variations. These variations are nor good nor bad, just different.

Example: different hair colour, skin colour, height, behaviour

Divergent evolution

A single population must be separated into subpopulations, and each subpopulation must encounter different selective pressures. As each subpopulation evolves on its own, they develop different and unique traits. If the differences are so vast that the subpopulations will not breed with each other, then speciation has occurred.

Examples: Polar and grizzly bears, wild boars and pigs

Convergent evolution

When organisms live in the same environment and experience the same selection pressures, they develop traits that are similar to each other.

Example: dolphins and sharks' colouration and dorsal fins, parrots, treefrogs, and other colourful animals in rainforests.

Homoplasies

Traits that are shared by unrelated species that help them both survive

Example: dorsal fins, colourful colouration of animals in rainforests

Adaptive Radiation

A more extreme version of divergent evolution. The difference is that multiple species will be created. In order for this to happen, the original population has to experience extremely low selection pressures in order for there to be plenty of variation to create the multiple species.

Example: the evolution of lions, tigers, jaguars, panthers, and cheetahs, Darwin's finches

Coevolution

Coevolution: when 2 species living in close proximity to one another evolve so their traits aid in each other's survival

Examples: Leaf cutter ants and their fungus, bumblebee's fuzz and roses, hummingbirds evolved to hover since their plants are weak and the length of their beak and the tubular flowers.

Species

A group of organisms that can breed with one another and produce a fertile offspring

Homologous features

A body part that is similar in an unrelated species

Example: forelimbs of mammals like cats, humans, bats, and whales

Vestigial features

Features that are not important and don't serve a purpose but are still there.

Example: appendix, dewclaw, whale and snake pelvis

Analogous features

A feature that performs the same function as another but has different origins or anatomical structure.

Example: bird and insect wings

Missing Links

The transition species

Example: Archaeopteryx, transition from reptile to bird, Ichthyostega, transition from fish to early amphibian

Sexual dimorphism

Differences in physical characteristics between males and females of the same species.

Example: female spiders are bigger than male spiders, female peahens aren't bright like peacocks.

Endemic Species

Species that are unique to a particular area

Example: Geographical isolation like islands can lead to new evolutionary pathways

Koalas, kangaroos, platypuses, galapagos turtle

Did humans evolve from apes?

No they did not, we share a common ancestor and then evolved separately

Is evolution the development of characteristics in response to need

No, because traits are controlled by genes, not needs

Is evolution the theory of origin of life on the planet

No, evolution explains what happened after life was created

Is evolution the change from simple to complex organisms

No, because sometimes organisms evolve from complex to simple to better adapt to their environment.

Did Darwin come up with the idea of evolution

No, he came up with a mechanism to show how evolution works (natural selection)

What is evolution

The change in populations over time

Immutable

Earth and life on earth was created in their present forms and couldn't and wouldn't change.

The greeks

They understood the basic concepts of adaptation and picked the best horses and fruits to breed. Plato believed species were striving toward their perfect form, or Eidos

George Leclerc

Theory of Degenerative forms: He believed god created the perfect forms for animals, but then life kept changing

Jean Baptiste Lamarck

His theory of parallel evolution and the inheritance of acquired traits theories were dismissed, but his theory that all species evolve in response to their environment and pass on their changes are still used.

George Cuvier

Catastrophism: he was the first to study fossils and show extinction. Series of catastrophic events wiped out populations and were replaced by new ones

Charles Lyell

Uniformitarianism: The same processes that occurred in the past still occur today.

Hutton

proposed that the Earth was millions of years old due to slow geological processes

Malthus

If the human population continued to grow unchecked, there wouldn't be enough living space for everyone.

How did the scientist´s work influence Darwinś ideas of evolution

Darwin travelled for 5 years on the HMS Beagle from 1831 to 1836 and went to the Galapagos

He noticed the patterns of diversity, how some fossils resembled living organisms while others didn't, and the islands had different climates which led to related organisms having different features (Galapagos finch beaks)

Darwin's Theory of Natural Selection

1. Variations exist between individuals of a species

There are different types of flowers, and humans are different from one another

Darwin's Theory of Natural Selection

2. Variations are inherited from parents but can also be enhanced.

Even though there are variations in species, these variations come from our parents because the chromosomes of the parents are mixed to create a new different offspring. Not only do you get your variations from your parents, but the variations can also be enhanced. For example, if a tall couple had a child, their child could be extra tall.

Darwin's Theory of Natural Selection

3. Populations produce more offspring than can survive on the available resources

Animals keep reproducing and populations keep growing, which causes limited resources and high selection pressure

4. Differential Survival

Differential survival is when there is something different about certain individuals that make them have a better chance of survival than anyone else in their population.

Variations that increase reproductive success will be more common in the next generation.

Differentiate between natural and artificial selection

Natural Selection is when nature selects which traits are advantageous and which ones aren't. The Organisms that survive and have the advantageous traits will reproduce so the next generation has more of those traits.

Examples of natural selection are how rabbits evolved to be faster, how giraffes necks grew longer, and how mountain goat's hooves changed to adapt to its environment

Artificial selection is when humans select which traits are advantageous and which ones can go into the next generation. The next generation will have more of the traits humans want to be passed on.

Examples of this are how humans created many dog breeds, and how cabbage and broccoli were made.

Stabilizing selection

when the normal trait is selected for, while the 2 extremes are selected against.

Example: infant birth rate: infants under weight and over weight can die

Directional selection

Directional: when 1 extreme is favoured over the other extreme and the normal

Example: Peppered moth

Disruptive selection

when the 2 extremes are favoured over the normal

Example: Himalayan and grey rabbits can camouflage, but white rabbits can't

Sexual Selection

when females choose which traits are passed onto the next generation

2 types: Intersexual and Intrasexual

intersexual selection

When females choose males based on their characteristics

intrasexual selection

when males fight for a female to show they have good genes.

Lines of evidence

What is the significance of the trunk and branches in the tree of life?

The trunk represents the most recent common ancestor, and the branches represent the individual evolutionary pathways

Where are the most primitive, recent and closely related species on the tree?

The oldest species are near the root, the most recent are at the tips of the branches, and the closely related species share the most recent common ancestor.

How do the following contribute to the evidence for evolution: comparative anatomy, fossils, geographical distribution, embryology, biochemical similarities

Comparative anatomy: if all living things come from a common ancestor, we should see similarities at the structural level

Fossils: if all living things come from a common ancestor, there should be links between species in the fossil record

Geographical distribution: If all living things come from a common ancestor, then organisms living in a particular area must have either immigrated from a nearby area or evolved from species that were already there.

Embryology: If all living things come from a common ancestor, then there should be similarities in embryological development

Biochemical similarities: if all living things come from a common ancestor, these should be similarities at the molecular level

Importance of whales in the understanding of evolution (from video)

Whales evolved from 4 legged land mammals, which is why theyŕe so important when understanding evolution