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Selection in Evolution

Added Sep 14, 2015 •

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hi sister Anderson in this video I'm going to talk about selection most of us are familiar with match reflection in the work of Charles Darwin will talk about that but I'm going to talk about to other forms of selection book artificial and sexual selection in this video when you're trying to use the word confusing for the best analogy I can come up with is thinking back to your days playing kickball are playing baseball when you were young and they have everybody line up and then Captain who they want on their team in and hopefully you didn't get Pickle I say I hope they don't do this in elementary anymore but that's selection selection when someone is choosing or something and choosing who is the strongest the fastest and then those that are chosen install you just get to natural selection and artificial selection honey you don't get Apache Jeans On to the Next Generation before you can have selection and you have to have the ratio of two graphs of variation in human height and so does a purple is going to be males and then this yellow is going to be female until an average male in the US maybe around 5 feet 8 average female going to be around 5 to 3 but we have a few people they're going to be much shorter than that to people that are going to be like 6 a.m. 7 feet tall and variation in nature we see that same thing so these are playing with these in class basically you plan come up in 3 days coming one and a half day so you can figure out you're going to be very late the number flowers how tall they are a little trichomes on the side so how many of those they have until you have to start with variation just like in that kickball exam when you get a chance based on that variation it's a basically selection we could break down in this concept map collection can either be artificial selection next Wednesday going to be when humans make the choice of who what teams did pass to the Next Generation and then natural selection take place in the environments collection we could break down into ecological natural selection not going to be that run-of-the-mill survival of the fittest differential reproductive success that your a million and then another type of natural selection is sexual selection that's when females are making the choice as far as what teams go on to the next Generation we could break that down into turn an intro into the rest of the podcasts are going to be about will start with artificial selection will end with sexual selection so let's there with artificial selection so let's say this the mom dog and she has a bunch of puppy will basically what we can do is we can choose which puppies we want to pass their genes On to the Next Generation forgot how we created a Chihuahua and a Saint Bernard by just choosing the traits that we want and the dogs breathing no to create the Next Generation and the Next Generation the next don't like killing dogs hit that we don't like basically worth choosing the ones that we do like and we're allowing nose to breed and pass their genes On to the Next Generation humans have been doing this from the beginning of Tosh the basically once our agriculture start then we start selecting traits that we want and we've been doing this housing near the Norman Borlaug is somebody who most of you don't know but he's known as the father of the Green Revolution in other words we were under duress on our plan you are running out of food we weren't able to produce enough food to feed everyone and so that started in them 30 40 50 the aunt it's basically Norman Borlaug was a farm and what he did is produced a number of different traits of Wheat and started by working in Mexico until he produce weed upper kabali was able to produce wheat two times pretty sweet a bigger brains on the top by doing artificial selection he also when they grew Too Tall they fall over and so then you hybridize man with not shorter kind of a mutant that had a short stocks in so they could have a lot of seeds on that instead of the results of that we were able to increase wheat yield play a look at it by the working on Norman Borlaug another we took production of weed on our planet 1950 up to 1990 and up to 2010 mini fool not through artificial selection selecting the traits that we want until when humans are making that choice based on variation we call that artificial selection ecological selection is a form of natural selection where nature makes the choice in this is first described by Darwin's along with sexual selection and basically to break it down into three things that can happen to a bell-shaped curve the first of those is going to be called directional selection so imagine we have this is variation so we're going to have one end and one until we get extreme that most of the averages are going to be in the middle and to let they change takes place in ecology change take place ecosystem how organisms are going to be selected for or against into an example could be the Witch of the glacier Lily Glacier Lily come up after the snow lead and so basically they'll start to come out right when the snow melts and then they're going to do pollination that makes the Next Generation the basically going on right now is that the climate of getting warmer and warmer and warmer and so what's happening well as it gets warmer and warmer and warmer that the glacier lilies that come out right here I'm going to do very well for the glacier Lily that happened to come out a little bit earlier I going to do better until we're going to see directional selection in other words we're going to see this the move in One Direction and so how does that work basically work by if you're greater Lily that man comes out much later you're going to die because it's going to be way too hot so we get a push in this Direction that's directional selection we also have stabilizing selection the great example of that if we think of this Redline as before why do most babies weigh around 7 lb well if you were to be born and weigh like 1 lb back in the day you die you were premature and you didn't survive the 10 pound baby in river to be born right here you're going to get the sock in your mom and your jeans are going to die and your mom jeans are going to die we're not going to pass that on to the next generation and so basically what we have for having collections for killing on either side of the Celtic and so that's going to squeeze Avail pictures gather you can happen is if we think of this me about paper maybe the ones in the middle are doing that well but the ones on the extremes are doing well example of that well remember those first pitches on Galapagos arrive there when it started feeling different niches they started eating different foods in to let they want fees on a small fee onesies on a big seed basically we get disruptive diversifying to watch it now what kind of mentally happen is that can split into two species and so basically this is all natural selection the the the rooms that are selected using organisms that survived pass their genes On to the Next Generation made sense to everybody at the time of the Darwin but the thing that would puzzling was sexual selection to let me tell you the story of the whiptail lizard whiptail lizard lives in the desert Southwest they're camouflaged well that was interesting is it they don't have any mail they only have females in the certain species of which a lizard to how they reproduce my things basically what they do with they make a parthenogenesis we called it when that cell is going to be just like every other cell in the lizard except it can spawn a clone of itself until every female in that area is a clone of every other female lizard in the area so they basically gotten rid of male they might because you're female Ray we could get rid of all the mail and then like to be easy but there's problems here and since they're all clone than any disease that might Target one of them is going to Target so basically there's no variation there's no selection and her the reason we have males is to provide new jeans to our in other words female that share their DNA with a male produce offspring that are not like them so that produce variation and said that led to what sexual selection the missing the Darwin for a while in fact he quoted as saying the side of a peacock just makes me ill because he didn't understand why you would have these real l things in nature if they're always going to be selected for ones that sit well in their environment and other would be better going to slow them down how to make him easier to be caught in nature it's a basically what he said long was this idea of sexual selection and sexual selection females are choosing which they're passed on and we can go to the Next Generation and so basically we could break that down into inter and intra sexual intersexual I remember this Interstate goes from state-to-state to supposed to between states intersexual is when a female is choosing a male based on characteristics that they intersexual the female peahen is choosing a male that has the brightest of feathered because if he has genes that can make bright feathers he altered they're going to make offering offering that are able to survive and so she's mating with him not just because he's impressed by the color but she's impressed by his mean and so cute do that as well until Angelina Jolie when she choosin Brad Pitt basically she's looking at all the characters to come the outside and she saying oh he jeans or maybe he's going to be able to produce offspring that have jeans intrasexual intra means between and so that's going to be fighting between it within an individual stats into an example of that if you like these elephants field battling throw hair on the female or like bull elk in Montana wolf subtract control a harem of female near fighting within now it's a basically what goes on there is the female just kind of sit back they wait until that male dominate all the other males if you can win that fight then he's going to have good genes he's also going to be able to produce fertile offspring so in both these cases is the female the take me to Troy it's not nature it's a female and once we have a trait that really is a good indication of genetic Health it has a tendency to go out of control until sometime suggested in humans the brain that stop in other words females are choosing a mate based on how good their genes are in a good indicator about is your brain and someone you asked me Mills weather attracted to a lot of the time it's not physical characteristics all those those are very important you know does he make me laugh cuz you really do care of me and these are really good judges of hugs of house to review what do we have got three types of selection artificial is in human chew natural The Logical natural selection can be when the environment chooses and then sexual selection is when the female and why do they get it shoes well damn mortal they carry the eggs they have a limited number of big lots of times and make sure they have to take care of the young and so is more important of the female think that toy so that's election and I

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Selection in Evolution

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