Patterns of evolution Flashcards
What are patterns of evolution (the main 4), what does patterns of evolution mean?
1) Adaptive radiation
2) Divergent evolution
3) Convergent Evolution
4) Co-evolution
Patterns of evolutions: How does changes within organisms happen in/follow a specific pattern?
What is adaptive radiation? (General defintion) (+ An example)
The rapid evolution of a single species into many new speciies, filling a vareity of formerly empter ecological niches. (Each speices devolped by adaptive radiation fills a different ecological niche, because there are a vareity of new resouces available)
–> Why do they look similar? because it has a very recent common ancestorior (esstientally the same animal) with a different ecological niche. (All these speicies are very similar and only differ in one specific thing, that makes them unable to reproduce and create viabile offspring)
–> this difference is because of their HABITAT/ENVIRONMENT/ECOLOGICAL NICHE
–> Different roles in the habitat = different environment = different selective pressures,
—> Ability to exploit the environemnt = exploitation of resources and creation of preferences.
—> EXPLOITING ENVIRONMENT MEANS ADAPTING TO IT. SO WHEN YOU HAVE A ROLE IN THE ENVIRONMENT, YOU MUST ADAPT TO IT.
–> Finch birds have many different species/types (i.e medium tree finch vs large tree finch vs small tree finch)
–> How did adaptive radiation play a role in this? A lot of competetion with food originally, when they moved there was no competetion of food (less birds/other species eating the same food as these birds) and MORE resources, therefore finches with smaller or larger bills did not have to fight for there seeds but rather is was readily avaiable for them. So they filled that SPECIFIC ecological niche, and evolved seperately from the medium bill
NOTE: this happens in a relatively rapid timeperiod, because it is usually caused by the drastic change in environment to an organisms. (moving, a natural disaster, etc)
What does adaptive radation lead to? / what is the outcome?
-> Less competetion (More vareity of species/different speices, means that there are less orgianisms that you are sharing your resources with)
-> Increased biodiversity (the more different species you have, the more alleles you have to work with, because all of these organisms are different)
What does ecological niche mean?
Habitate role/job
Niche: “role”
Ecological: “environment”
What is divergent evolution? (General) (+ AN example)
Large scale evolution of a groups (population of organisms that share a common ancestor) into many different forms.
–>They all look very distinct/different
–> Why? despite being related to each other they are exposed to increasingly different environments, therefore there are many selective pressures/environmental stressors put on them. (differences in environment = change, with more time, changes can accumulate)
“Diverging away from each other”
–> Happens over a long period of time, because all of these species have evolved from a common ancestor that exist millions of years ago.
+ For changes to accumulate you need a lot of time.
i.e. all the different types of rodents: rats, flying squirel, deer mouse.
(All originated from one organism, but put into different environments)
What is the outcome of divergent evolution? / result? (Explain it different/y [than adaptive radation] or in specifics to divergent evolution)
Competetion between species is minimized because all of these different speices need/are expose to different things (less overlapping) (New speices diverge to fill specialized ecological niches)
All species will evolve until most of the available resources are used, because using your resources means you are ADAPTING to your environement (constantly changing)
–> Results in overal biodiversity.
What are the differences between adaptive radiation and divergent evolution? (2 main oness!)
1) Time frame, adaptive radation is quick and rapid (A single ancestor diversifying into multiple species, NO ACCUMULUATION), while divergent is slow and gradual (Accumulation of changes overtime)
2) Adaptive Radiation, all different speciies look very similar to each other, while divergent evolution look increasingly different.
What is convergent evolution (what does it mean?)
(What are examples of convergent evolution?)
“Converging together”
–> Species of different ancestors/distantly related soecies evolve to have similar traits or features.
–> Two different species are within the same environment (EXPOSED TO THE SAME SELECTIVE PRESSURES)
(Same selective pressure = similar features/changes that make it easier to survive = therefore both will change/adapt in that way [/natural selection will favourite that trait in both organisms] = both organisms have that feature)
ie: Birds, butterfys and bats all have wings, but no common ancestor with wings, therefore all were exposed to an environment where they needed to fly. (ie: all needed to run away from pred, eat/read food, etc)
cati and eupherbia (both look the same but are in different parts of the world) (Both adapted in the warm temperatures)
What is the outcome/effect of convergent evolution?
1) Natural selection will favour the evolution of similar traits in similiar environments no matter the organism (These traits benefit/help you survive or reproduce = YOU WILL BE SELECTED)
2) Similar traits does not mean same speicies, all species have/retain districtive features that proove that they are distinctive/are different species.
What is co-evolution? An example + description
Two species that have evolved to become dependent on each other, evolving in response to the other species.
I:e orchid and moths (orchids pollen is down this long tube that only MOTHS can reach due to their long lips)
–> Usually seen in symbiotic relationships
What is the result of co-evolution?
-> A threat to one species could be a threat to the other (Because they depend on each other to live, therefore depending on each other to change/stay the same [if one changes, the other one must change too])
-> an extinction of one speices could lead to the extinction of another.
What does symbiotic relationship mean?
Benefiting both parties
What is human evolution (How is it different from animal evolution?)
How humans differ from other species due to the degree of our environement.
What are the 3 physical attrobuits humans have that are distinctivily different than animals?
Phylogeny wise, whach animal is the closest to a human
1) Large brain compared to body (Contribuits to our devolpement in sentient thoughts and ideas)
2) Hand dexterity/fine motor skills (manipulation)) and coordinations
3) Ability to multitask due to our legs.(bipedalism)
humans most recent common ancestor is chimpanzees.
What is cultural evolution? List the 4 main ones and how this distinguishes us compared to them
1) Language
2) Relgion/beliefs
3) artistic endavors
4) Domestication of other specoes
Culutral differences fully distinguish us from chimpazees, than our physical appearences (because we share 98.8% of our DNA with chimpanzees)
