Natural Selection
To be added to our last notes of evidences of evolution...
DNA Sequences Similar DNA bases/similar arrangement of nucleotides (ATGC)
Biogeography Organisms that live in a common area/similar climate
To do: In the back of your notebook... Make one page of the back of your notebook say the word “TRUE” in big letters” Make one more page of the back of your notebook say the word “FALSE” in big letters.
True or False... DNA can be used to see if organisms share a common ancestor.
Answer: TRUE! We use DNA to see how closely related organisms are...
True or False... Evolution means that monkeys will turn into humans very soon.
Answer: FALSE! Monkeys DID NOT turn into humans. We share a common ancestor with monkeys.
True or False... All organisms develop the same way as embryos until around 2 months later.
Answer: TRUE! All animals at first develop gills and a tail, they later lose them.
Natural Selection Organisms with favorable traits will survive, reproduce, and pass those traits onto their offspring. Nature Does this Not the organism
Natural Selection In order for natural selection to occur, there must be inherited variation.
Survival of the Fittest Also known as Natural Selection
Fitness An organism’s reproductive success Organisms with greater fitness reproduce and pass on their traits to their offspring
Adaptation A population becomes better suited to its environment which increases chances of survival. Doesn’t happen overnight. Individuals DO NOT change, POPULATIONS change. More examples: White rabbit in snow, duck web feet for swimming, skunk with smell, porcupine, chameleon to change color
Mutation A change in DNA. This is the only way of introducing a new trait to a species
Recombination Genes are rearranged during meiosis to create unique offspring (increased genetic variation) EX: Crossing over
Speciation Formation of a new species When 2 groups of species become so different they can no longer breed. Polar bears and brown bears.
Artificial Selection Selection by humans for breeding of useful traits. HUMANS DO THIS, NOT NATURE EX: Pure breed dogs AND artificial crops
True or False... Fitness means that an organism can lift a lot of weight.
Answer: FALSE! Fitness means that an animal can successfully reproduce and carry on their blood line.
True or False Adaptations can happen overnight.
Answer: FALSE! Adaptations takes years (hundreds, thousands, and even millions of years)!
True or False Mutations lead the way for natural selection to occur...
Answer: TRUE!