Evidence of Evolution (03) (Evolution) Flashcards
What is the evolution pipeline (3)
Genetic informaton passed down (creation of genetic diversity) –> Genetic information is mutated (neutral, benefitual, and harmful) –> (leads to) Species overtime changing (accumluation of benefitual mutations)
What are the 5 evidences that proove that evolution exisit?
1) Biogeography (Past and present geographical distrobution of organisms)
2) Fossils (Imprints of organisms overtime within rocks)
3) Anatomy (How the anatomy/body parts of organisms change)
4) Embryology (The devolpement of embryos, and how we look similar in the beginnning compared to the end)
5) DNA (If your DNA is similar to another organisms, you guys are most likely related to each other)
What is biogeography?
And which person made a connection to biogeography and evolution? (What was there hypothesis?)
What is biogeographys connection to DNA?
Biogeography: The study of the past and present of the geographical distrobution of an organisms
Darwin: Observed species within remote islands, and saw that many of these speicies were unique.
On remote islands, species were “unusual” (Did not appear on the mainland of the closest contiental land mass). Animals also behaved unusally, often fearless and interacted with humans.
Connected to DNA:
closely related species were geographically near each other. Therefore why were these island species unique (the question/hypothesis)?
(The resembance of organisisms is due to the theory that they all stem from a single organismsm/one source, therefore organisms that look similar and live within the same geographical area, means that they are descendants of an ancestor that lived in that area)
Why are species that are physically close to each other genetically related?
-Plate tetonic movement: Earth use to be this one large landmass, so animals could be near each other and breed, etc. But as plates moved, animals seperated, then evolved on their own.
–> The affects are still apparent because we can find fossils/anmals of the same species accross the world
(Birds in Canada are more genetically related to bird in the USA than India)
What was Darwin’s Hypothesis to his observation? (Give specific examples)
-> The population of remote islands are filled with species that arrive by water or air. (Species that can only fly or swim, because that was the only method of transportation that could cross the large body of water)
->After species came on the island, they evolved into new species (as a response to the environment, by exploiting the materials)
-> Species on the island have a resemblance to the species of the nearest contiental land mass. (If it is a greek island, then the animals look like lgreek animals) (same descendants)
This means that..?
-> There was no native ammphibans or mammals.
-> Unqiue species on the island, because they evolved independently from the mainland.
How was Darwins hypothesis tested?
–> To test hypothesises, you always have to try to proove it wrong.
-> His thought process: If his hypothesis is correct, all his observations should appear on other islands.
Within another island (hawaii) he saw the same things
-> No amphibians/mammels
-> Unique birds and insects
-> Lots of reptiles and marine animals
–> This tested for the potiental of the idea that mammels could have arrived to the island but did not survive (went against the idea that they just couldnt get there)
–> Despite these oberservations it was not enough (It wasn’t a test)
The real test: Introducing mammels into the islands (to see if they could survive)
Results:
1) They thrived
2) There was devasting impacts on the native species of the island. (they were pray)
WHICH MEANS WHAT?
Mammels could survive, they just could not get to the island.
What are homologous features? (Part of anatomy)
-> Organisms/features within organisms that are similar in structure however functon different.
->Example: Hand on bats and hands on humans are structurally similar
(However, bats and humans are extremely different, bats can fly while humans cannot)
Mammals have almost identical # of bones and feature arrangements to each other, however they are not identical within function.
How does homologous features relate to evolution?
-> Closesly related speices share common ancestors (You are able to see the devolpemental process, and you can see how organisms change)
What are Analogous feautures? (Part of anatomy)
Features that share the same or similar function, however they are structually very different. (They also have completely different origins)
Examples: Wings of insects and wings of birds.
->Structurally different, but both served the purpose of flying.
Embryology and its connection to evolution:
–> Connected to homologous features…
In early developmental stages - embryos of all vertebrates possess a short bony tail (they look virtually the same)
Human embryos also have gill slits even though we do not have gills by the time we are born (needed to survive within the belly of mother)
-> We all were the same in early devolpement, and with time, we changed and evolved.
What are vestigial feautures & Anatomical oddities? (related to anatomy)
Vestigial features: features on the body that are no longer being used or served little to not function. (Had a purpose in the past, but they no longer do)
–> Human wisdom teeth!
–> Happens with time, no mutations affect the organism/no changes to the DNA
Anatomical oddies (similar to vestigial featurues):
features that serve an unusal purpose or have structure that is difficult to explain.
->Whales with hipbones, even tho they cannot walk
Emphaszies/connects to evolution, because it looks like the animals had changed overtime to not used these features anymore/ (the environment changes overtime)
Competetion with population: Who created this theory?
What does this theory mean? How does this related to the environment? Natural selection meaning?
The theory that populations are limited by size and environment because of food supply, by Thomas Malthus.
-“Survival of the fittest”
Why cant population grow indefinetly?
-> Some spieces produce only 1-4 offspring at the time (Humans)
-> Some species can produce large amounts of offspring but its easier for many of them to die
–> they are mostly limitd by their resource
->High competetion of survival between species for food, water,etc (ESP between the same species because they eat the same things)
–> Relation to “naturally selected/good mutations” because if there is less genetic diversity theres is more competetion, therefore you are relying on youyrs genes to make you the fastest, strongest, etc for food/
What are pseudogenes?
Structures that are no longer functions because of a mutation, these genes serve no useful purpose to the organism.
-> Dolphins have 500 pseudogenes related to small (they cannot smell, but they have these unfunctioning genes)
-> Humans are mutated, and can no longer produced vitamen C (not a harmful mutation)
–> A showcase to the evolution of food. (Cavemans ate meat and did not get enough vitamen C, now we have more food, and we dont need to produce vitamen C)
How do homologous feautures relate to evolution?
How do anaologous features relate to evolution?
Homologous feautures: descendants of the same ancestor (therefore at one point in time they were identical speices), but then once introduced to a new environment, they evolved differently. Which explains why their structures are similar (was once the same thing) but now they function differently (according to their environment)
Anaologous features complete opposites to homologous features: Species were orginally different (they are not descendants of the same ancestor) but they were introduced to the same environment. Therefore their structures and different, but their functions are the same because they live within the same environment.
