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Video transcript

we're now going to start looking at ecology which is just a study of how life interacts with other life or how living things interact with each other and their environment and so you could think of it is well how is life interacting with living things so that's the technical term often given as biotic factors biotic factors you have the word bio in their signaling life or nonliving things a biotic factor a is the prefix often for not so a biotic is not living a lot living factors and those are just a technical terms but if you even think about yourself as you watch this video you are in an environment you are interacting with it there are many abiotic factors around you that you might notice the the air that you are breathing the temperature your access to water but there's also biotic factors even if you think you're in a room alone you're not fully and you're not completely alone there is bacteria around you that you might not see there might be other forms of life you might have a plant in the room those are the biotic factors that you are interacting with that plant in that room might be producing oxygen that you are then breathing or you're producing carbon dioxide which that plant is able to fix and grow and it might be interacting with abiotic factors like sunlight - in order to then it uses in photosynthesis in order to fix the carbon we study all of that in some depth in biology and really ecology is is a bit of a synthesis of a lot of what we are if anything all of what we learned in biology because it's taking life up it's studying life at another level where it's not just the individual organism anymore but it's not even just the the population or the community but we're talking about an even bigger system that is incredibly complex and that's why it's a really interesting thing to study now all of these images here are things that folks would associate with an eco system over here you have a coral reef and some of the life is obvious you see the coral you see the fish here but there's also life that you're in not seeing there there's going to be bacteria in this water that's not visible at least in this picture and the abiotic factors are going to be things like the water temperature or frankly just even the existence of water or the salt content of the water or other minerals that are in the water these pictures over here you don't necessarily see the animal life but there is for sure going to be if you were to dig into this grass or look look through this bushes you will find animal life you will find insects you'll find other animals the trees are life so that's going to be part of the ecosystem and we would if we r studying ecology we would think about well how do these trees interact with the water interact with the other species how do they provide shelter for them or food or or how are they dependent on the other life in some way to grow same thing for in this case the mushrooms how does how is the fungus living on this this tree branch or on this in conjunction with with the moss and whatever else all of this is a study of ecology the study of ecosystems now when folks are talking about ecology they like to talk about different scales and so let's now think about the different scales within an ecosystem or even beyond an ecosystem so I have some pictures that if you watch a wildlife show you're you typically see some images like this and so since we at least are familiar with it at least at least on TV hopefully we get to visit this at some point in our life now let's just think about the different characters here on the different ecological scales so at the most basic scale is the individual so let me write this down you have the individual so if we were talking about these elephants the individual would be one individual elephant right over there now the next scale is is the population the next scale is the population and if we were to stick with our African savanna theme right over here the population you have an individual elephant the population would be the members of that same species that live in that area so in this case the population would be what least include these elephants that we see in the picture there might be a couple of elephants that are off the picture and I should say in particular these are going to be the African elephants so it's the members of the same species that are living in the same place and it's up for the the classifier or the scientists wherever studying it to define what do we mean by living in the same place we might define it as the people you know the people the the elephants that live within a few miles of this watering hole you might define it as the elephants that live within a broader area it could be you know that live in East Africa or South Africa or whatever it might be and so defining the population is all the members of the species that live in an area but that area is up for definition now the next level up is the community is is the community and that is all the living things that might live in that area however we define the area so for example if this line and this giraffe lives in the area that we use to define the population they would be members of the community so let me circle them so they would be members of the community and it wouldn't even just be the big animals that you see here it would include all the life that is in that area so it include the vegetation that is in the area it would include the bacteria would include the fungus it will include any animals that are living inside of this water that you see there now if you go even one more level of a kind of inclusion then we go to the ecosystem so then we go I'll go down here then you go to an ecosystem and what an ecosystem is it's all of the living things in that community so all the living things in an area and then you're also adding the nonliving things the abiotic factor so you're including the rock and the air and the weather and the clouds and the water itself that is part of that watering hole and a lot of times you might think that the the abiotic factors well they should they for sure effect they for sure effect the the biotic factors if you don't have wall serve the temperatures too cold or too hot it might be hard for a certain type of life to thrive but it goes both ways the biotic factors affect the abiotic factors we have oxygen in our environment due to life on Earth they might also affect the the various the chemical composition of certain parts of the the abiotic factors say the water or the the soil or whatever else and if you want to get a level above an ecosystem then sometimes you'll hear people talk about a biosphere biosphere which is you can think of it as a meta ecosystem or oftentimes in my head I view it as a fully it contains all of the ecosystems that are in some way connected to each other so a fully enclosed fully contained ecosystem and biospheres are actually well I guess the most the the most famous biospheres are the most the one that we're typically referring to is we could refer to the whole earth as a biosphere it has multiple ecosystems and once again the ecosystems it depends what the researcher wants to define is an ecosystem it could they could define it as you know just something around a certain River and a certain area just like that or they might define the ecosystem as a broader region but all of the ecosystems in the world are part of the biosphere that we know as that is part of Earth and we it's self-contained because we don't think that there are that many influences from outside of the earth although even there we have to give some credit to the Sun that is providing abiotic factors for sure we wouldn't have life on Earth as we know it without the Sun and there's also things like the moon the gravitational effects you could consider that an abiotic factor without the tides we would not have life as we know it but one thing that's really fun as many of you all know I enjoy science fiction is to think about well what kind of biospheres could you have even if you if you think about beyond the earth and this is a depiction here this is actually from NASA's website of how humans could could create biospheres outside of the planet it's this interesting thing where you know that's that's you know quote unquote land up here I would be artificially created and that you would rotate it so that there's a the the perception of gravity but anyway the study of ecosystems the study of biospheres the study of ecology in general is incredibly incredibly fascinated because when you have all of this complexity each living thing is incredibly complex and in fact if you want you could even sometimes consider part of a living thing as an ecosystem in and of itself if you were to look even on the surface of your hand you have bacteria living there that's dependent on you in some way and you might actually benefit from the bacteria or actually get hurt from the bacteria in in some way so there's all sorts of different scales but once you start factoring everything in together becomes these incredibly beautiful complex often balanced sometimes in balance systems that have emergent properties that start to that that start to have behaviors or that and I want to use that word very loosely that that are that are somehow described or I guess you could say properties that somehow describe the ecosystem as a whole
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