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- Chapter 13 Species diversity: land and sea - ScienceDirect
There are 34 phyla living in the marine realm, 17 in freshwater, and only 15 on land At the class level, 77 occur in the sea, 35 in freshwater, and 33 on land 11 The ratio of less than 200 000 marine species to around 12 million terrestrial species means that the ocean contains less than 2% of the species on earth 12
- 2. 3: Diversity of Life - Biology LibreTexts
Species diversity refers to the number of different species in an ecosystem or on Earth as a whole This is the commonest way to measure biodiversity Current estimates for Earth's total number of living species range from 5 to 30 million species Genetic diversity refers to the variation in genes within all these species
- What Do You Know About Life on Earth? | AMNH
These extreme microbes live off chemicals spewed out of deep-sea volcanoes They don’t need sunlight to live! Scientists now estimate archaea to be 50% of the species found in the open ocean But the exact number of archaea species is unknown Check out these other kinds of archaea that live in different habitats
- This new, complete tree of life shows how 2. 3 million . . .
This circular family tree of Earth's lifeforms is considered a first draft of the 3 5-billion-year history of how life evolved and diverged You can save this article by registering for free here
- One million species threatened with extinction because of . . .
One million of the planet’s eight million species are threatened with extinction by humans, scientists warned Monday in what is described as the most comprehensive assessment of global nature loss ever Their landmark report paints a bleak picture of a planet ravaged by an ever-growing human population, whose insatiable consumption is destroying the natural world […]
- Estimating How Many Species Humans Have Driven to Extinction
They then extrapolated the data to all known species, calculating the number of extinctions if all known species had suffered a similar extinction rate consistently over 500 years This led them to estimate 150 to 260 extinctions a year for every million species on Earth (E MSY)
- All of Humanity Weighs Six Times as Much as All Wild Mammals
Around 40 percent of the total mass of all wild land mammals can be traced back to 10 species, four of which are deer estimates, total 25 billion At 0 5 million metric tons for bats and 1 1
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