when a population decreases significantly, the species can become extinct, endangered or threatened
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DECREASING POPULATIONS
When a population decreases significantly, the species can
become extinct, endangered or threatened.
Extinctions
99.9% of all species that ever lived on Earth are now extinct.
Extinction appears to be a natural cycle and part of our changing Earth, but the cause of early extinctions are a cause for concern.
Mass Extinction Dinosaurs were believed to be extinct
due to a meteorite crashing into Earth.
Are humans causing the next mass extinction- the sixth in the history of life
on Earth?
Extinct Species
An extinct species is one that has died out and left no living relatives.
Species become extinct due to due to climate change, disease, destruction of habitat, natural disasters and development into a new species.
Dodo Bird The dodo bird was found on the Island of
Mauritius in 1505.
The last dodo bird was killed in 1681.
Quaggas
Quaggas were hunted to the brink of extinction in the mid 1900s.
The last Quagga died in the Amsterdam zoo in 1883.
Mastodons
Mastodons roamed the Earth 15 million years ago.
They became extinct about 16,000 years ago.
Endangered Species Endangered species are species that
numbers are so small, they are in danger of becoming extinct.
The Miami Blue Butterfly
The Miami butterfly lives mainly in Florida
Their numbers are believed to be only around 50 to 60 adults.
Gray wolf of Yellowstone
The gray wolf numbers are declining rapidly.
They are being killed by farmers and hunters.
Leatherback Turtles
Leatherback turtles weigh 1,000 pounds and have roamed the oceans for hundreds of years.
It is now on the endangered list.
Threatened Species
Threatened Species are species that are vulnerable to become endangered in the future.
Polar Bears
Polar Bears are threatened due to global warming and the changing of their habitat.
Orca Whales
Orca whales are residents of the Pacific Northwest.
Due to population decline, many realize they are a species threatened to become extinct.
Marine Turtles
Although marine turtles have been around for millions of years, they are now threatened.
Reasons for their decline are poachers and predators pillaging their nests as well as habitat degradation by human impact.