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Send diverse calculated

hi and here is a quick tutorial about biodiversity and calculating the diversity of an area using Simpsons index now there's a couple different types of formulas to calculate so I'm going to push play on this tutorial slideshow and we'll get started all right so before we get into it what is diversity well if you go into an area and you see a small area you see just one or two species in there obviously that means it has a low diversity however if you go into an arrogantly see many different kinds and here's the key many of each of those kinds of species on maybe 50 red ants 60 black ants 50 spiders 70 snakes sound like Indiana Jones doesn't it a lot of each species that is what diversity is referring to so let's go through and do a couple examples before I go any further let's just quickly point out that there are several different ways to calculate Simpsons index the IB in their syllabus for biology they'll put this equation here in the upper left and this shows Simpsons reciprocal index I personally prefer using Simpsons index of diversity in the upper right because the result will give you an answer between 0 & 1 which is a lot easier to make sense of in my opinion all right to do a quick google search of the other ultimately you are getting to the bigger the number the more diverse the lower the number the less diverse the folk they're they're both similar in that sense now so d is diversity and let's quickly make sense of these variables and it talks about the total number of species that you're sorry total number of everything that you will find in that area so those snakes that spiders those red ants that I mentioned earlier to count everything that's your big n little n lowercase n will refer to the number of each individual species so how many red ants that's one number that you'll keep how many black ants so it's another little n is ill key now let's go through and do a quick example so here's four three different quadrats a quadrat is just a square sample area so one is filling up with little alien faces and then we have two others the right is filling up with a lot of different types of faces and the middle square the middle quadrat is filling up with three different species we have the red the purple and yellow with the shades on three different species six of each of those species alright now let's go through and calculate one at a time you might want to pause here and try to just get a guesstimate on what you think is the least diverse and which is the most diverse based on the big in and little in that we have in our equation so let's move on here will calculate the one with all the alien faces first so just going through the equation you'll see that I have 36 alien faces and so 36 times itself another lowercase n 36 times 36 minus one I'll explain that minus one in a second then we go to the next face in the next one over there are two yellow faces so two times itself two minus one and then we go to the next face the purple which is 1 1 times itself minus one now your might look at that last part of the equation there and you might say well 1 times 1 minus 1 which is 0 so 1 times 0 is 0 right perfect you're correct this is why we see the minus 1 in the original equation at the top the minus 1 is a bit of a fail safe to say that if we find just one species out there in a quadrat we're assuming that that's a ran and it won't count it's it's some somewhat of just an oddity that came into our sample and is probably migrating or moving through so we won't count it in this diversity sample and that's the way that we erase that one let's go through the math now by the way the 39 was 39 total faces in there so 39 times 39 minus one we do the calculation and we end up with something like this and don't forget to do it one - a lot of people forget that at the bottom we have to start that one - at the beginning of the equation and I end up with D equals 0.15 okay so what does that tell me well that's actually a probability this is very low diversity by the way and probability says but if I were to pick two randomly out of this square and I picked any two well there would be a 15% chance that I would pick different ones okay that's a little weird but think about it in terms of the lower the number the less diversity and that's because one of these species dominates you can see the alien faces really dominates and there's not a lot of anything else so that starts to maybe make sense let's go through one in the middle here now I'll go through the math we have six of each species and we have 18 total species so that's how we put it into our equation and we do the math and I just need some very simple calculator on the side of my computer here to do this I hope I did it right we'll see maybe someone will comment if it's wrong and I end up with 0.71 which is 71 percent chance that if I were to pick any two of those it'd be different so that's pretty high diversity now let's go to the last one and here we go you can push pause and give this one a try if you like algorithm math now and I found seven of one species 7 of another species 6 7 species six of another and three of those aliens on 29 total in there and I go through and I calculate that out and I subtract it from the original one and I end up with E - that's very high that's a very high diversity so eighty-two percent chance that they would be different if I picked any two now what you could end up doing is you could actually start to graph these on maybe doing a transit away from human habitat and lay down quadrats as you go down that transact and you could see how biodiversity changes as you move away from a human habitat I'd be a nice very quick experiment you can do with really good results probably and just to finish we just quickly compare the different diversity indexes here and this C's here these different examples you see that zero is low one is high maybe you can visualize what that might look like right so we have a lot of different kinds and a log each kind in the highest number I hope that helps someone and send me a comment if you need any support with this hopefully I can help Thanks