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Course: Middle school biology > Unit 6
Lesson 2: Biodiversity and ecosystem healthBiodiversity and ecosystem health
Google ClassroomReview your understanding of biodiversity and ecosystem health in this free article aligned to NGSS standards.
Key points:
- Biodiversity is the variety of species in an ecosystem.
- Biodiversity decreases when species go extinct, or die out. Extinction often happens when organisms can no longer survive because of changes to their ecosystems.
- A decrease in biodiversity can be the result of human actions. For example, human actions are leading to habitat loss and climate change. These, in turn, are causing a decrease in Earth’s biodiversity.
- When an ecosystem loses biodiversity, it doesn’t function as well. So, scientists often look at how complete an ecosystem’s biodiversity is in order to measure the ecosystem’s health.
Want to join the conversation?
I am wondering how mosquitoes interact with the other species in the ecosystem. How??(8 votes)
Great question! Mosquitos typically are prey for other insects, birds and spiders. This helps the spiders and other creatures that eat mosquitoes eat, but also keeps the mosquito population stable and prevents it from skyrocketing. Mosquitoes also feed on animal blood. As far as interactions go, the main interaction is a food source for other animals and insects while also sucking blood out of animals, hope this helps!(24 votes)
We need to help animals stay. ALM (animal lives matter)(20 votes)
im not a vegan but i agree with you. animal lives do matter, but we can eat some animals too. like we just learned about food webs.(2 votes)
omg humans are killing animals(7 votes)
I don't want to be rude, but we are very good at making species go extinct. But mutations can be a risk to us.(9 votes)
why do mosquitoes exist i hate them so much(7 votes)
I don't actually know.(8 votes)
What happens if humans stop interacting with other species? Will the "safety net" break completely, or will there be a less major problem or even no problem?(7 votes)- i personally believe that there would be less major problems and more animals would "thrive", not in all cases cause there could be other animals that depend on us like dogs or other house pets. Also other animals that are prey to other animals/predators(7 votes)
If a species that is not native to the area suddenly arrives, can that harm the ecosystem? What are they (the new species) called?(5 votes)
Good question!
When a non-native species arrives, they are generally called an "exotic species". If they harm the environment (which they often do), they are called "invasive". They often disrupt food webs by over-eating a native species. Invasive species are generally fast reproducers, because they wouldn't survive long if they weren't. Because of this, they take up a lot of space meant for native species. They also might overrun an ecosystem.
Hope this helps!
Here are some KA articles & videos on this subject:
https://www.khanacademy.org/science/ap-biology/ecology-ap/disruptions-to-ecosystems/a/invasive-species
https://www.khanacademy.org/science/ap-biology/ecology-ap/disruptions-to-ecosystems/v/introduced-species-and-biodiversity
Have a good day!(11 votes)
- This gonna help because it makes me smarter.....(7 votes)
How does biodiversity exist(4 votes)
Simply because there are different species of living things on the planet.
Hope this helps!(6 votes)
- but there something i dont get. Lets say that the rabbit population is decreasing then the predetors eating rabbit start to decrease but when the predetors decrease, the rabbit population will increase meaning the it will go in a cycle over and over again. so if a prey population gets closer to extinction so do the predetors but then the prey get bigger again. So doesn't that mean that ecosystems/biodiversty can fix themselves?(5 votes)
- But actually, the majority of extinction is caused by humans.(3 votes)
- How does biodiversity exist?(4 votes)
Short answer: Biodiversity exists because some areas can support many species.
Long answer: Over many millions and even billions of years of mutation and natural selection, new species form. In some areas, only a few of these species can avoid going extinct, due to factors like harsh conditions. However, some areas, like the islands of Hawaiʻi, allow many species to develop and survive, which is how biodiversity can exist.(2 votes)