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Biodiversity is a key concept in ecology and has importance on both local and global scales.
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Biodiversity is the degree of variation of life.
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Or put it more simply, the number of different individuals and life forms in an area.
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Scientists usually measure biodiversity on either genetics, species or ecosystem levels.
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For example, if you wanted to measure the biodiversity of beetles on a global scale,
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you would find there are over 350,000 known species of beetles on the planet.
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However, if you want to measure the biodiversity of beetles locally, you might find only up to 10 or 20 species.
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The reason for this difference is that biodiversity varies greatly with the location, habitat and species being surveyed.
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In general terms, biodiversity tends to be highest at the equator and decreases at higher latitudes, i.e. as you get further away from the equator.
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Knowing this information, where would you expect to find the habitats with the lowest biodiversity?
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Pause the video and have a think.
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Habitats at the equator, such as tropical rainforests, usually have the highest biodiversity.
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So if you thought habitats at the North or South Pole, such as the polar desert, you're correct.
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It's important to know that biodiversity is not a static measure but is responsive to numerous factors, including climate change.
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In fact, global biodiversity is generally thought to be declining right now.
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Biodiversity has declined in the past and the total of five major extinction events have occurred.
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Currently we are in the planet's sixth major extinction event, known as the holocene extinction.
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There are many proposed reasons for the current drop in biodiversity.
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Some of those reasons are anthropogenic, meaning caused by humans.
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Anthropogenic factors include things like introduced or invasive species, such as the introduction of rabbits to Australia.
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Human induced hybridisation, such as in plants to create optimal species of crop.
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Over harvesting of resources and global climate change caused by human activities.
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While humans are responsible for all of the current extinction events,
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there is good evidence to suggest that humans are affecting the world on a global scale and causing the loss of many important species.
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The loss of biodiversity could have catastrophic effects on our society and even result in the loss of our food crops.
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For example, bees are in huge decline and they are extremely important in the pollination of many plants, including our crops.
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There are lots of ways we can reduce biodiversity loss and even increase biodiversity,
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such as managing our land better, growing more than one crop and including plants that encourage insect diversity.
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And also creating cities with space for other species.
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We shouldn't just focus on the rural areas, urban places can do their bit.
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By increasing the local biodiversity, we can help the environment to sustain itself and give it a better chance for standing the effects of global climate change.
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A healthy and diverse ecosystem can withstand and recover from disasters.
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Biodiversity is an important topic that affects us all.
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As a global community, we need to take action to protect our biodiversity on both local and global levels.
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Here are just a few of the free services a healthy biodiverse ecosystem provides us with.