A squat, round bird that waddled to get around. An elephant-like mammal with shaggy fur and enormous tusks. Both animals died out long ago. Which would you choose to bring back from extinction?
Which species would you bring back from extinction?
Learning Objective: Students will gather and use information about two extinct animals to support an argument.
A squat, round bird that waddled to get around. An elephant-like mammal with shaggy fur and enormous tusks. Both animals died out long ago. Which would you choose to bring back from extinction?
DODO BIRD
Daniel Eskridge/Stocktrek Images/Science Source
The dodo was about 3 feet tall and weighed up to 50 pounds. Its wings were too tiny for it to fly!
WHEN AND WHERE THEY LIVED
Jim McMahon/Mapman®
The first dodos lived several million years ago. They became extinct sometime around 1690 A.D. They lived only on the African island of Mauritius (maw-RIH-shuhs), in the Indian Ocean. Mauritius has dense rainforests, rocky cliffs, and white sand beaches.
WHAT THEY WERE LIKE
Dodos are related to today’s pigeons. But unlike pigeons in the U.S., dodos on Mauritius had no natural predators! Their ancestors didn’t need to fly to escape being hunted. So over many generations, their wings became tiny. Their bodies evolved short, thick legs. Dodos used their large beaks to eat fruits and nuts.
WHY THEY BECAME EXTINCT
In 1598 A.D., Dutch sailors landed on Mauritius. Dodos weren’t used to being hunted, so they didn’t hide from humans and were easy to catch. Sailors reported that the birds tasted oily and gross. But the rats that snuck on and off the sailors’ ships loved to eat dodo eggs. Within 100 years of humans’ first recorded sighting of a dodo, the birds were all gone.
REASONS TO BRING THEM BACK
Bringing back the dodo could help the ecosystem of Mauritius return to the way it was before humans changed it. Dodos spread seeds in their droppings, helping forests thrive. Today the government of Mauritius is taking steps to remove invasive species, like rats, and to allow some of its farmland to become wild again. If we brought dodos back, could they help these wild areas grow?
WOOLLY MAMMOTH
MARK GARLICK/Science Source
Woolly mammoths could reach 12 feet in height and weighed about 8 tons. That’s heavier than four cars!
WHEN AND WHERE THEY LIVED
Woolly mammoths evolved about 300,000 years ago. By 2000 B.C., they were extinct. They lived during the Ice Age, a time when northern Asia, Europe, and North America were mostly covered with snow and ice.
WHAT THEY WERE LIKE
Today’s elephants are adapted to warm climates. But their ancient cousins could survive temperatures as low as -58°F (-50°C)! Woolly mammoths had two layers of thick fur. They also had giant tusks—each 15 feet (4.5 meters) long—to dig food like leaves and twigs out of the snow.
WHY THEY BECAME EXTINCT
Woolly mammoths disappeared around the same time the Ice Age ended. Melting snow and ice turned the cold grasslands where mammoths lived into wetlands. Mammoths couldn’t find enough food and eventually died out.
REASONS TO BRING THEM BACK
Bringing back woolly mammoths could help protect the Arctic. How? When woolly mammoths were alive, they scraped up snow while eating. That allowed freezing air to chill the soil beneath. Today Earth is warming faster than ever, causing Arctic soil to thaw. Some scientists think woolly mammoths could protect this habitat by helping the soil stay frozen! But Earth has changed a lot in 4,000 years. Would mammoths survive?
Which would you bring back?
Which would you bring back?
Which would you bring back?
1. PREPARE TO READ (10 minutes)
Make an initial choice and explain the reasoning behind it.
2. READ AND EVALUATE (15 minutes)
Gather information and discuss text evidence.
3. RESPOND TO READING (20 minutes)
Write and evaluate an evidence-based opinion.