Level 1 - Absolute Beginner
Coral reefs are like underwater cities. Many fish live there.
A new study looked at reef-building corals. It says about 44 out of every 100 species are in danger.
In 2008, about one third were in danger. Now more are in danger. The main reason is climate change. The sea is getting too warm.
The scientists say the real number may be even higher.
- coral
- a tiny sea animal that builds hard reefs
- reef
- a long line of coral under the sea
- species
- one kind of animal or plant
- danger
- a chance of harm
- climate
- the usual weather in a place over many years
- warm
- a little hot
- study
- careful research
- sea
- the large body of salt water
Level 2 - Elementary
A new reassessment by the IUCN says about 44 percent of reef-building coral species are now threatened with extinction. In 2008, the figure was about one third.
A scientist from the University of Portsmouth took part in the work. The main threat is climate change, which makes ocean water too warm for corals. The authors say the true figure is probably higher.
Corals are small animals. When the water is too hot, they lose the colorful algae that live inside them and turn white. This is called bleaching.
Other studies this week looked for hope. In Hawaii, researchers found that some corals handle heat better than others. In a lab, bleached corals got their color back after touching healthy corals for five days. It is not yet known whether this can help whole reefs.
- reassessment
- a new check of an earlier result
- threatened
- in danger of being lost
- extinction
- when a whole kind of animal or plant disappears
- bleaching
- when coral loses its color because of heat
- algae
- tiny plant-like living things in water
- figure
- a number
- researcher
- a person who studies a subject
- whole
- complete, all of it
Level 3 - Intermediate
About 44 percent of reef-building coral species are now threatened with extinction, up from roughly one third in 2008, according to a reassessment by the International Union for Conservation of Nature that involved a scientist from the University of Portsmouth.
Climate change is identified as the dominant pressure, as rising ocean temperatures trigger bleaching, in which corals expel the symbiotic algae that feed them and give them color. The authors caution that the real proportion is probably higher, since some species are poorly studied.
Separate research this week offered a more nuanced picture. A Florida Atlantic University study of Hawaiian corals found that heat tolerance differs among species, among populations and even between colonies of the same species. In a laboratory experiment, bleached cauliflower corals regained their color after five days in direct contact with healthy fragments.
Researchers stress that the lab result has not been tested at reef scale, so it should not be read as a rescue plan. Still, variation in tolerance gives conservationists something to work with, because the hardiest colonies might help restock damaged reefs.
- reassessment
- a new evaluation of an earlier judgement
- dominant
- the strongest or most important
- symbiotic
- describing a partnership in which both sides benefit
- expel
- to push out
- nuanced
- showing small but important differences
- tolerance
- the ability to endure something
- colony
- a group of living things that grow together
- conservationist
- a person who works to protect nature
Level 4 - Advanced
Roughly 44 percent of reef-building coral species now face a heightened risk of extinction, up from about a third in 2008, according to a reassessment by the International Union for Conservation of Nature that drew on a University of Portsmouth scientist.
Climate change emerges as the overriding threat: marine heatwaves provoke bleaching, whereby corals eject the symbiotic algae on which they depend for food and color. The authors acknowledge that the true figure is probably higher, partly because data on some species remain thin.
Concurrent research complicates the bleak picture without reversing it. A Florida Atlantic University study of Hawaiian corals found that thermal tolerance varies across species, populations and even individual colonies, suggesting a reservoir of resilience. A separate laboratory experiment showed bleached cauliflower corals regaining their pigment after five days in direct contact with healthy fragments.
Scientists are careful to note that the laboratory finding has not been tested at reef scale, and that heat-hardy colonies cannot offset emissions-driven warming on their own. Yet conservationists see in such variation a possible basis for selective restoration, in which tolerant stock might repopulate degraded reefs while the larger task of cutting emissions continues.
- heightened
- increased or made greater
- overriding
- more important than anything else
- whereby
- by which
- concurrent
- happening at the same time
- reservoir
- a large supply of something held in reserve
- resilience
- the ability to recover from difficulty
- offset
- to balance out or cancel
- degraded
- reduced in quality or condition
Talk about this article with KatePractice this story's vocabulary in a real spoken conversation with your AI tutor