Middle school biology - NGSS
Biodiversity and ecosystem health: a Hawaiian Islands case study
Biodiversity describes the variety of species found in Earth’s terrestrial and oceanic ecosystems. The completeness or integrity of an ecosystem’s biodiversity is often used as a measure of its health. Created by Khan Academy.
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- Why is she saying "Ha-v-aii" instead of Hawaii? It's confusing me.(4 votes)
- some Hawaiians also pronounce like this,
so it's not completely strange.
hope this helps.(13 votes)
- Okay so what exactly is biodiversity in other places the Hawaii?(5 votes)
- Biodiversity is a measurement of the number of living species in a certain area.
In the Amazon Rainforest in South America, another biodiversity hotspot, the biodiversity includes around 2,500 animal species and about 80,000 plant species!(11 votes)
- Would the Earth be better without humans at all?(6 votes)
- probably, humans have been the reasons of many species decline. Humans also take up way more space and resources than we need.
fact: every single person on the planet could fit in the small country of Belgium.(6 votes)
- Since islands are 'hotspots' for biodiversity, what is the place that has the least biodiversity?(3 votes)
- The middle of Antarctica would be a satisfactory answer for that question, as it sees no plants and the only animals it sees would be wandering seabirds that got lost.(2 votes)
- Why does she pronounce "W" like "V"? Is there any real reason to this or is it just some weird accent related thing?(3 votes)
- It is just her accent.
Hope this helps!(1 vote)
- Okay so what exactly is biodiversity in other places the Hawaii?(1 vote)
- Biodiversity is anywhere where an ecosystem is, the question is how much is the biodiversity in a place.(1 vote)
- its Hawaii not havaii lady say it right(0 votes)
- some people in hawaii say havaii they both mean the same thing(5 votes)
- Science, also widely referred to as Science Magazine, is the peer-reviewed academic journal of the American Association for the Advancement of Science[AAAS 2] (AAAS) and one of the world's top academic journals. It was first published in 1880, is currently circulated weekly and has a subscriber base of around 130,000. Because institutional subscriptions and online access serve a larger audience, its estimated readership is over 400,000 people.
Science is based in Washington, D.C., United States, with a second office in Cambridge, UK.
The major focus of the journal is publishing important original scientific research and research reviews, but Science also publishes science-related news, opinions on science policy and other matters of interest to scientists and others who are concerned with the wide implications of science and technology. Unlike most scientific journals, which focus on a specific field, Science and its rival Nature cover the full range of scientific disciplines. According to the Journal Citation Reports, Science's 2020 impact factor was 47.728.
Studies of methodological quality and reliability have found that some high-prestige journals including Science "publish significantly substandard structures", and overall "reliability of published research works in several fields may be decreasing with increasing journal rank".
Although it is the journal of the AAAS, membership in the AAAS is not required to publish in Science. Papers are accepted from authors around the world. Competition to publish in Science is very intense, as an article published in such a highly cited journal can lead to attention and career advancement for the authors. Fewer than 7% of articles submitted are accepted for publication.
cover of the first volume of the resurrected journal (February–June 1883)
Cover of the first volume of the resurrected journal (February–June 1883)
Science was founded by New York journalist John Michels in 1880 with financial support from Thomas Edison and later from Alexander Graham Bell. (Edison received favorable editorial treatment in return, without disclosure of the financial relationship, at a time when his reputation was suffering due to delays producing the promised commercially viable light bulb.) However, the journal never gained enough subscribers to succeed and ended publication in March 1882. Alexander Graham Bell and Gardiner Greene Hubbard bought the magazine rights and hired young entomologist Samuel H. Scudder to resurrect the journal one year later. They had some success while covering the meetings of prominent American scientific societies, including the AAAS.[AAAS 3] However, by 1894, Science was again in financial difficulty and was sold to psychologist James McKeen Cattell for $500 (equivalent to $15,660 in 2021).
In an agreement worked out by Cattell and AAAS secretary Leland O. Howard, Science became the journal of the American Association for the Advancement of Science in 1900.[AAAS 4] During the early part of the 20th century important articles published in Science included papers on fruit fly genetics by Thomas Hunt Morgan, gravitational lensing by Albert Einstein, and spiral nebulae by Edwin Hubble.[AAAS 4] After Cattell died in 1944, the ownership of th(1 vote)
- just got back from hawaii...(0 votes)
(waves splashing) - [Narrator] When you think of islands, you might think of pristine beaches and palm trees gently swing along with a warm breeze. Sounds like paradise. And as a scientist, islands are my kind of place for research. Islands are very beautiful and they also have a lot of biodiversity. Biodiversity can be described as the variety of species in an ecosystem. Now, some ecosystems have higher biodiversity than others, but all ecosystems have a variety of species that interact in specific ways with one another. Islands have such a variety of species that they're often called biodiversity hotspots. They're home to so many diverse species, much more so than the continents. There are nearly half a million islands around the world, but they only make up about 5% of the Earth's land area. Yet, islands are home to 20% of the world's plant species and 15% of all mammal, bird and amphibian species. Many of these island species can only be found on one island or within a group of islands. For example, you can only find the 'i'iwi, a honeycreeper bird species, in the main Hawaiian islands in the North Pacific Ocean. (birds chirping) The 'i'iwi are important pollinator species for Hawaiian plants, including the 'opelu and and the 'ohi'a. Pollination is an essential part of plant reproduction allowing plants to produce their fruits and seeds. While the 'i'iwi feeds on the sweet nectar of these plants, this bird also helps to support the next generation of 'opelu and 'ohi'a. These and other types of interactions are happening all the time between species in an ecosystem. You can think of biodiversity as a sort of safety net, with each species as a knot, and the ropes between knots as their interactions. The diversity of species and their interactions, hold the net together allowing the ecosystem to function. Plus, the relationships between species are often unique. For example, the 'i'iwi has a special curved bill, and it's evolved to feed on the nectar of very specific flowers that are similarly curved. Like the 'opelu. Now, even though the 'i'iwi is highly adapted to its environment, if something happens to the 'opelu or 'ohi'a and the plants start to decline, it can spell disaster for the 'i'iwi. When an ecosystem changes so much that a species can no longer survive? That species may become extinct or die out, causing biodiversity to decrease. And unfortunately, many of Hawaii's honeycreepers and overall biodiversity have been lost through extinction. In the past, there were at least 20 other species of honeycreeper found across Hawaii, but many of them have become extinct over time. If we return to our analogy of biodiversity as a safety net? Whenever a species goes extinct it's like a knot becomes undone and parts of the net start to fall apart. A decrease in biodiversity is often a result of human activities which is especially clear in the Hawaiian Islands. In the last few hundred years, agriculture, grazing, logging and development have taken almost half of Hawaii's forest cover. And along with it, a big part of its biodiversity. Humans have also brought non-native animals like rats and feral pigs to Hawaii, which have changed or destroyed native habitats. Plus, new diseases and climate change have led to the extinction of many Hawaiian species. When an ecosystem loses biodiversity, it doesn't function as well. If 'ohi'a starts to disappear from Hawaiian forests? It's not just the 'i'iwi that loses an important food source, but the entire ecosystem is affected. In fact, scientists often look at how complete an ecosystem's biodiversity is in order to measure the ecosystem's health. The safety net of biodiversity is supported by having lots of different species, which allows the ecosystem to cope with natural disasters like drought, storms and disease. With more biodiversity, ecosystems are stronger and more resilient so they can recover quickly. But, with less biodiversity, ecosystems become more vulnerable. I told you a lot about how Hawaii is losing biodiversity, however, there is cause for some hope. The nene, or Hawaiian goose, nearly went extinct. There were less than 30 birds in the wild 50 years ago. Now, thanks to lots of conservation work to improve the habitat for those species, there are over 3,000 nene throughout the islands. We humans are part of earth's biodiversity too. We are components of the ecosystems we touch. So if we have the power to hurt these ecosystems, we have the power to protect and heal them too. Aloha.