Tuesday, February 7, 2012

Muddiest Point

Hi guys, i don't get what radioactive dating is, I am just really confused with the whole subject of it. Can someone explain it to me please? thanks(:

Muddiest Point

Hi, guys I am still confused about convergent evolution. I don't understand the difference between convergent and regular evolution. Please help, Thanks

Muddiest Point

Hey guys. I'm a little confused why Lucy, Australopithecus, is not our ancestor, but is our relative. I'm also kind of confused about how Darwin developed the theory of natural selection. If you can help me out that'll be great! Thanks!

Muddiest Point

My muddiest point is adaptation. What is it, and how does it relate to the principles of fitness and Darwin's observations? Also, what is survival of the fittest? I looked over the definition, but it just doesn't make sense.

Thanks!

Muddiest Point!!!

Hi everyone,

I'm confused on what convergent evolution is. If someone could help that'd be great!!

Thank you!

My Muddiest Point

I dont uderstand why Lamark believed that animals had a desire to change. What evidence did he collect to make him believe his hypothesis?

Wednesday, February 1, 2012

Scribe 2/1/12

Hey Guys! The first thing we did today was turn in our Lab 38.

Next, we took some notes on Genetic Variation. Here they are:
  • In terms of genetics, evolution is the change in frequency of alleles in a population's gene pool.
  • Natural selection leads to change in gene frequency.

Genetic Drift
  • Changes in the gene pool of a small population due to chance.
  • Occurs when a small group colonizes a new habitat- founder effect.

Speciation
  • Species- group of organisms that interbreed to produce fertile offspring under normal conditions.
  • For new species to form, reproductive isolation needs to occur, where organisms don't interbreed and gene pools separate. This can occur because of:
  • Behavioral Isolation: when populations have different courtship rituals or other behaviors.
  • Geographic Isolation: when populations are separated by geographic barriers.
  • Temporal Isolation: when two or more species reproduce at different times.

Next, we did Lab 40, from our biology lab books. We worked with our lab groups and we each got four grasshoppers and a ruler. We had to measure the femurs, or the top parts of the jumping legs. After we measure all of the femurs from the four grasshoppers, we compared all of the data from the whole class. We used this data to create a graph and see the variation in the grasshopper legs. Below is a picture of the grasshoppers we had to use to measure the femurs.



Homework:
  • Finish Lab 40
  • Read 19.2

Next Scribe is ... Janie!