Question

Describe each of the types of natural selection.

Answer 1

I kind of have an idea for what they are, but clarity would be greaattt. xD

Answer 2

Stabilizing Selection-- The extremes are selected against.
*Example: height; mostly beings tend to the average height- not too many really short ones or really tall ones.

Directional selection-- One extreme value is selected for.
*Example: speed; faster is always better so a population will tend to get faster over time.

Disruptive selection-- The extremes are both selected for.
This type of selection is not as common as the first two.
* Example: Prey-type animal with distinctive markings which the predators know will over time move away from the norm in both directions.

Answer 3

Okay, I was right. Thanks so much!:D

Answer 4

no probs

Answer 5

a good way to visualize this is by doing looking at their graphs.

Answer 6

Yes, I've been looking at those, too. They do help.:)

Answer 7

http://assets.openstudy.com/updates/attachments/51b019bbe4b05b167ed2afcd-nincompoop-1370584898004-22_lecture_presentation.ppt

Answer 8

http://assets.openstudy.com/updates/attachments/51b019bbe4b05b167ed2afcd-nincompoop-1370584912844-23_lecture_presentation.ppt

Answer 9

Wow, thanks man.:D

Answer 10

Could one of you help me with one more detail? @nincompoop @Ashleyisakitty

Answer 11

I also uploaded practice test on evolution and natural selection
http://openstudy.com/study#/updates/51b019bbe4b05b167ed2afcd

Answer 12

o-o ... thanks?xD

Answer 13

Include the role that each plays in increasing or decreasing variation within a population.

Answer 14

I'm assuming that, for instance, stabilizing would increase the population?

Answer 15

those three types that @Ashleyisakitty provided give the effects on the variation of particular species within population.
it is not about the population itself increasing or decreasing. it has something to do with the variation of genotypes/phenotypes.
this is why the graph helps a lot because it gives you more than just the definition, but also the effects.

Answer 16

OH. Okay. Excuse me, I'm not very good at bio.. ._.

Answer 17

did you download the powerpoint presentation I provided?

Answer 18

observe the attachment

Answer 19

so these are characteristics based on what variation of phenotypes (physical attributes) are selected.
stabilizing would be the selection to eliminate both the extreme types of phenotypes favoring the intermediate type;

disruptive would be the selection to eliminate the intermediate type and favoring the extremes;

and directional would be the selection to eliminate one extreme among different types of variation.

Answer 20

let me know if there are more things to clear :D

Answer 21

HUGE help!! Thanks so much! I already gave Ashley the best response, but you have definitely provided the best detail. Thanks so much!:D

Answer 22

i just basically reiterated what she said :( but I thought with few words that will make it easier to understand.

by the way, since you are in these types of variation selection, have you gone through other population selection and speciation?

Answer 23

I know; both of your answers are equal in helping me complete my assignment. But, your answer provided information that I can easily pull up from Keynote.

I'm currently studying evolution. So yes, I am going through population selection and speciation.