Evolution 2 Flashcards
_________ drive evolution
mutations
How we behave in society is very much influenced by __________
genetics
What can cause gene mutation to occur?
- Mistakes in gene transcription
- External factors such as chemicals or radiation
Must mutations are _______ or _______ and therefore will be selected against.
harmful, fatal
When can a mutation be selected for?
When it’s beneficial and fives the individual an advantage over others
What is genetic drift?
The disappearance of mutations due to random events
Why are beneficial mutations not always selected for?
Genetic drift
How long can it take for a beneficial mutation to actually propagate in a population?
Millions of years
What are 2 ways natural selection can improve the adaptability of species? Describe them.
Mutation and variation. They are mainly differentiated by timescale
Variation: Natural Selection of favorable traits that already exist in the population. This can be as fast as a few generations
Mutation: Natural selection of novel beneficial mutations. Can take 100’s of generations as these mutations are rare.
What is kin selection?
An evolutionary strategy that prioritises the reproductive success of the organisms relatives even though it may cost their own life.
Kin selection is a form of ______ ______, where it combines the number of kids produced with the number of individual who can ensure the production of offspring by supporting others
inclusive fitness
Why does kin selection work?
Even though the individual’s ability to reproduce is lowered, it increases the chance of its close genetic relatives.
A population with significant genetic variation in traits i more likely to survive dramatic changes in the ________ or encountering a deadly ________
environment, disease
Epigenetic modifications are responses to the ________. They can persist for a few generations
environment
What are some reasons to understand evolution?
- Understand drug resistant bacteria and viruses
- Understand disease and development
- Animal and crop propagation
- Conversation guide and mitigate climate change
- Manage common pool resources
- Understand where we come from
- Understand social behaviour
Why is it important to finish the entire antibiotic treatment even when you feel fine?
At the beginning of the treatment, the drug begins to kill of most of the bacteria and you start to feel better. But bacteria that have a better tolerance for the drug, do not die off as quickly, and are selected for. These partially resistant bacteria need a longer treatment time to be killed.
If you end early, these bacteria can reproduce, and create even more resistance in the long term
What is a common method to combat bacterial resistance?
Using multi drug cocktails that target different bacterial pathways. It’s unlikely for a bacteria to protect against multiple antibiotics at the same time.
How did humans evolve to combat the cold?
- Increase metabolism, heat production, and fat
- Modified behaviour by wearing clothing and seeking shelter
Most populations can adapt to _____ term changes without changing genes, and instead by up-regulating latent genes
short
What species is an example of low genetic diversity due to habitat loss, hunting, and several bottlenecks?
cheetahs
What are some examples of climate change driven evolution?
- Salmon migrating earlier
- More brown coloured owls in forests that have snow for shorter amounts of time
- Coral interacts with algae less sensitive to warm ocean waters
What are some examples of species that may go extinct due to climate change?
Great tit birds, as they are hatching there babies after caterpillar season, since caterpillars are maturing earlier due to the warmer spring weather
What is a bottleneck event?
An event that causes many members of a species to die off
Why do species that undergo a bottleneck event usually go extinct?
It reduces the genetic diversity to below a critical point and they will not be able to adapt even if the numbers come back up
What are some change that could cause extinction?
- Climate change
- Food availability
- Pollution
- Introduction or disappearance of other species
Why is extinction not always bad?
It is the driving force of evolution. It’s only bad if more species are going extinct than being created.
What are 3 levels that populations can respond in with regard to changes in the environment?
- Plasticity: Individuals change their appearance and metabolism depending on season
- Adaptability: Over generations, individuals who are better fit to the new environment are selected for and become dominant
- Mutations: Over thousands of generations, novel mutations might improve survival and be selected for
What is an example of plasticity?
Foxes having a winter and summer coat. Winter is white, summer is brown for camouflage purposes
What is an example of adaptibility?
Peppered moths in England. Before industrial revolution, white moths are dominant as they blend with birch better. After trees were blackened with coal soot, black moths became dominant is they blend in better
What is an example of a mutation that propagated due to changing environments?
Mutations of white fur were beneficial for bears when they migrated to the arctic.
Eventually, polar bears evolved to form a separate species
It’s important to use our understanding of evolution to reduce the rat of ________ for different species
extinction
What factors should be considered when making decisions that affect biodiversity?
- Maintain population diversity
- Some species will go extinct and it can’t be helped due to lack of adaptability
- Which species should we focus on
- Look at evolutionary history to see which species have a better chance to survive and focus our efforts there
__________ species is often a part of normal natural selection and evolution. Modern organisms arose because one species invaded and ___________ other species
Invasive, outcompeted
What are 2 types of invasive species?
Type 1: Species migrating from nearby locations in response to changing environments. This is normal, but can be prevented by reducing pollution and stopping climate change. Otherwise, these species will just become the new native species as they are likely more suited for a warmer environment
Type 2: Species artificially introduced from far away locations, usually by humans. Can have devastating effects on the local ecosystem.
What is an ecosystem?
A geographic area where different organisms live together
What is the implication of ecosystems in relation to evolution?
When one species evolves, other species evolves with them in a symbiotic-like fashion. Overall, the ecosystem is balanced.
What is an example of an artificially introduced invasive species?
Bringing 20 Canadian beavers into Argentina’s island to bolster the fur trade. As the beavers had no natural predators, they damaged 50% of the forests.
Are are artificially introduced invasive species so dangerous?
They disrupt the balance of the ecosystem that has not evolved to deal with these kinds of species.
In their native lands, the species is kept in check from predators and other species, but not in the new land.
Even with artificially introduced invasive species, ecosystem eventually reach a balance where the new species either _______ or _______, but not before it causes lots of damage
integrates, dies
What are some examples of invasive species in BC?
American bullfrog
Eastern grey squirrel
Common carp
Japanese beetle
