hey guys it's your first video lecture of the semester I know you've been excited about it so let's go ahead and jump right in please make sure you are filling in your notes organizer as I go through the PowerPoint today's topic is going to be the principles of ecology this is a topic very familiar to you so I'm not going to spend a lot of time talking about some of these things if you need extra help feel free to pause replay or restart at any time so if we're going to talk about ecology we need to talk about what ecology is ecology is the study of the interactions between organisms so organisms with other organisms but also between organisms and their environment these terms you'll hear me use a lot you probably already know what they mean biotic factors versus abiotic factors biotic factors are the living factors in an ecosystem bio means life the abiotic factors are going to be the non-living factors so biotic factors normally we think of plants and animals but don't forget about bacteria protus fungi and then for the abiotic factors those are going to be things like water sunlight temperature rocks and soil okay so looking at this lovely picture of a tropical rainforest on your notes organizer see if you can identify three examples of biotic factors and three examples of abiotic factors okay um the biosphere is about several kilometers above the Earth's surface and about several kilometers below the ocean's surface so basically the biosphere is the place on Earth where you have life so the biosphere is made up of small smaller eological levels so going from smallest to largest that would be the single organism and then a population and then a community and then an ecosystem and then a biome and then all the biomes together make up the biosphere so we're going to talk about what each one of these um is and also examples of what's included please fill in your chart as we go through it so one single living thing is called an organism so our example we're going to go with a desert ecosystem here is going to be one individual rattlesnake a population consists of organisms made up of the same species so if our single organism was a rattlesnake our population would be a group of rattlesnakes a biological community is all of the interacting populations within that same area so remember our population was a group of rattlesnakes so all of the populations would be the rattlesnakes the lizards the coyotes the fungi the cacti the grasses all all of the biotic factors that make up the sorin desert so Community is all the biotic factors so going even bigger than Community you have the biotic factors plus the abiotic factors that would be your ecosystem so we have our community rattlesnakes lizards coyotes fungi cacti grasses but now also in an ecosystem we're going to have sunlight sand rocks and then of course the temperature of the sorin all the biotic and the abiotic make up the ecosystem and then we have all the similar uh ecosystems in the North American you know the West portion of of North America that are going to make up the desert biome so a biome is a large group of ecosystems with similar climates plants and animals and then of course all the biomes together that's everywhere there is life so that makes up the biosphere and there's a picture showing you that we're going from smallest to largest okay I am not going to spend a lot of time talking about the different biomes if you need extra help with that I am posting some PowerPoints to the blog feel free to look through those or any of the uh tutorial links that we used in class the other day but you do need to know what is used to classify a biome what makes a bioma biome it's having similar of these four categories precipitation temperature plants and animals sometimes you'll hear it as three major categories and that's because precipitation and temperature make up the climate so sometimes you'll hear climate plants and animals okay so those there are your major terrestrial biomes or land biomes here are your major aquatic biomes here's this lovely little pie graph showing you that you know of all the water that we have on Earth 98% of it is salt water only 2% of it is freshwater and then of that tiny little 2% most of that is glaciers and most of that is groundwater various small small amount are going to be lakes and rivers feel free to pause on this chart if if you need to uh get any of this extra information you can use this to help you fill in the chart that we did in class the other day you've probably seen all this information before in seventh grade I do want to make sure you know how to read each of these three graphs um so this top left graph here and these are questions on your notes organizer what biome would you expect to find at 150 cm of of rain and 10° C of annual temperature so use that graph to see if you can figure out what biome you would be in you'd be in the temperate deciduous forest right smack dab in the middle okay use this graph to to answer the question uh which biome would you expect to find closer to the Equator the temperate deciduous forest or the coniferous forest which is what they're calling the needle leaf forest okay so here is the equator here's increasing L latitude or it could be decreasing latitude just further away from the equator but you're going to have temperate deciduous forest before you have coniferous forest so you would expect to find the temperate deciduous forest closer to the Equator okay and then finally looking at that climatogram remember the bar graph is showing the precipitation for each month the line graph is showing the temperature so on your paper what what biome would you expect that climatogram to be from lots of rainfall every month pretty steady temperature but it's pretty warm so that would be the tropical rainforest okay there's some freshwater biome the different zones of the lakes and ponds here are the different zones of our marine ecosystems now obviously the most biodiverse zones whether freshwater or Marine are going to be the zones that are shallow and the reason for that is because there's sunlight there so the more sunlight the more producers you can have the more producers you can have the more consumers you can support okay couple of vocab terms before we move on you probably already have heard these words before a habitat is just simply where an organism lives a niche is the role that an organism has in its environment so our bumblebee here while we may not love them they do have a niche in the environment that they live in they are pollinators so that would be a role that it plays in its environment okay so we have communities remember those are all the interacting populations all the biotic factors and those are controlled by what's called limiting factors so anything that can restrict or control the size of a population is called a limiting factor a limiting factors so you can have water be a limiting factor sunlight food shelter space Predators prey all of those things can control the size of a population and then once you reach What's called the carrying capacity you've reached the maximum number of of of population that an ecosystem can support so looking at our graph here what do you think the carrying capacity of deer would be for this habitat or this ecosystem it's probably somewhere around 80 deer because once you get past 80 you can see the population begins to decrease and then it sort of floats around right at that 80 uh deer mark because then the limiting factors have kicked in they've sort of restricted the size of the population and you have reached your carrying capacity some limiting factors depend on the size of a population and other limiting factors don't so the factors the limiting factors that don't depend on the size of a population are going to be density independent factors this would be something like the weather the weather doesn't it doesn't matter what the size of a population is to affect the weather right or fires or air pollution or anything like that air pollution can control the size of a population but it doesn't depend on the size of a population density dependent factors however do depend on the size of a population so this would be something like disease disease is going to have a different impact on a population depending on the size of the population same with competition same with Predators same with parasites so where do these biological communities come from well they they come from a process called ecological succession this is a process where you replace one biological community with another and this is a result of the changing factors both biotic and abiotic in an ecosystem there are two types of ecological succession primary succession and secondary succession primary succession takes place when you have newly exposed rock which does not have have a top soil so how do we end up with newly exposed rock that doesn't have a top soil well that usually happens after a volcanic eruption or when you have the melting of a glacier or the retreating of a glacier then you have new rock so there are only certain things that can live on that newly exposed rock and those are called pioneer species things like lyans mosses liver warts they don't have Roots they don't need a lot of nutrients they can live and grow on that newly exposed rock and then they help to break the rock down form a little top soil layer now you can have these small plants start to grow they'll make a bigger top soil layer then you can have the grasses and then eventually the shrubs until you've got this nice thick top soil where you can support these nice big mature trees and then you can support a greater diversity of of animals as well secondary succession takes place when you have a newly cleared area but the top soil layer remains so you can sort of skip that pioneer species um section of succession so this usually takes place after something like a forest fire or a flood or a hurricane or a tornado the area is cleared out but the top soil remains so you just basically start off with small little plants that start to grow they get bigger then you can support grasses then you can Port support shrubs then you have your smaller trees until eventually you can have your larger trees here's a couple of other vocab terms for you that you're already probably familiar with competition competition does not mean fight I do not want to hear you say fight when we talk about competition competition simply means one or more organisms trying to use the same resource so competition can take place between plants plants in the tropical rainforest compete for sunlight they're not fighting each other you don't see a tree punching another tree so I don't want you to use that term it just means that organisms are trying to use the same resources the same limiting factors and then you have predation which is where one organism hunts and kills another the hunter is the predator of of course the hunted is the prey so in the case of our bird and our worm here the Predator would be the bird the prey would be the worm okay do you remember talking about symbiosis in seventh grade symbiosis is a long-term close relationship that exist between two or more different species living in an area there are three types of symbiotic relationships you have mutualism commensalism and parasitism on your little chart there Under symbols I want you to draw these little happy faces in sad faces and straight faces mutualism is when you have two happy faces whoops sorry commensalism is when when you have one happy face and one straight face parasitism is when you have one happy face and one sad face and you can tell from these symbols probably what these three different relationships mean so mutualism two happy faces is when both species are benefiting from the relationship this would be like the oxpeckers those little birds that eat eat pests off of Ze zebras so the zebras are getting these parasites taken off of them that's good for them and then the oxpeckers are getting food so they're benefiting from the relationship as well so the feeling is mutual they're both very happy that is a mutualistic symbiotic relationship commensalism a happy face and a straight face this is where one species benefits and the other doesn't benefit from the relationship but it's also not hurt from the relationship so that's our straight face so this would be an example of a bird um laying putting a nest and laying eggs in a tree the bird is benefiting because they're getting a nice protected space for their you know Offspring to grow and develop while the tree I mean the tree doesn't care whether the bird's nest is there or not doesn't take nutrients away from them or anything like that so that would be an example of commensalism happy face straight face then you have parasitism happy face sad face this is where one species benefits from the relationship while the other is harmed and an example would be like a tick living on a dog The Tick is getting food that would be blood so that would be the parasite that's the one benefiting from the relationship and then the dog would be the host the one being harmed it's having blood taken away from him obviously that's not good um it can diseases can be spread through the tick so that would be an example of a parasitic symbiotic relationship okay couple more words you're probably familiar with autotop versus heterotrophs um an autotop is another name for a producer and we talked about this with photosynthesis these are organisms which use energy from the Sun or other substances in order to produce food on their own food for the organism so this is like photosynthesis or chemosynthesis which we'll talk about but basically they make their own food they don't have to consume anything else a heterotroph is also known as a consumer that's what we are they have to obtain energy by consuming other organisms and there are different types of heterotrophs you've heard this before herbivores eat plants carnivores eat animals omnivores this is what we are we eat both plants and anim animals you have things like detrivores and scavengers that eat the remains or decaying portion of plants and animals then you he you have um decomposers which are slightly different because they break down the decaying matter externally and then absorb the nutrients internally whereas scavengers do everything internally so I'm going to stop here for today um you can leave the the rest blank for now we're going to do the rest in class I hope you're having a great day bye