Idea for Use in the Classroom
Share the infographic with students and discuss what defines a mass extinction.
Divide the class into two groups. Assign one group to come up with reasons as to why we ARE experiencing a mass extinction and assign the other group to give reasons as to why we are NOT experiencing a mass extinction. Give them a quarter of the class time to come up with their arguments using information from the infographic on previous mass extinctions, and then lead a debate for half of the class. When both sides have given their cases and rebuttals, come back together as a class to discuss the controversies surrounding the issue and why it is in fact a difficult topic. Ask: Over what time scale have Earth’s previous mass extinctions taken place? Ask students to come up with possible causes for the sixth mass extinction given the sources of past extinctions. As a class, come up with a list of ideas to help prevent the extinctions of current species.
acidic
Adjective
something with a pH less than seven.
algae
Plural Noun
(singular: alga) diverse group of aquatic organisms, the largest of which are seaweeds.
asteroid
Noun
irregularly shaped planetary body, ranging from 6 meters (20 feet) to 933 kilometers (580 miles) in diameter, orbiting the sun between Mars and Jupiter.
carbon dioxide
Noun
greenhouse gas produced by animals during respiration and used by plants during photosynthesis. Carbon dioxide is also the byproduct of burning fossil fuels.
comet
Noun
celestial object made up of ice, gas, and dust that orbits the sun and leaves a tail of debris.
Cretaceous-Paleogene extinction event
Noun
(66 million years ago) (K-Pg extinction) relatively brief time period in which a “global winter” led to the extinction of about 75% of all life on Earth. Also called the Cretaceous-Tertiary (K-T) extinction event.
Devonian
Adjective
geologic period between Silurian and Mississippian.
dinosaur
Noun
very large, extinct reptile chiefly from the Mesozoic Era, 251 million to 65 million years ago.
earthquake
Noun
the sudden shaking of Earth's crust caused by the release of energy along fault lines or from volcanic activity.
fauna
Noun
animals associated with an area or time period.
glaciation
Noun
process of a glacier carving out a landscape.
greenhouse gas
Noun
gas in the atmosphere, such as carbon dioxide, methane, water vapor, and ozone, that absorbs solar heat reflected by the surface of the Earth, warming the atmosphere.
habitat loss
Noun
the reduction or destruction of an ecosystem, making it less able to support its native species.
Holocene
Noun
having to do with the present geological time period. The Holocene Epoch began at the end of the last glacial period, about 10,000 years ago.
Jurassic
Adjective
having to do with the time period between 190 million and 140 million years ago, characterized by an abundance of dinosaurs and ammonites.
mammal
Noun
animal with hair that gives birth to live offspring. Female mammals produce milk to feed their offspring.
mass extinction
Noun
extinction event in which a large number of species go extinct in a relatively short period of time.
methane
Noun
chemical compound that is the basic ingredient of natural gas.
Ordovician
Adjective
geologic period between Cambrian and Silurian.
oxygen
Noun
chemical element with the symbol O, whose gas form is 21% of the Earth's atmosphere.
perish
Verb
to die or be destroyed.
Permian
Adjective
last geologic period of the Paleozoic Era.
Noun
base level for measuring elevations. Sea level is determined by measurements taken over a 19-year cycle.
toxic
Adjective
poisonous.
Triassic
Adjective
start of the Mesozoic era when dinosaurs first emerged.
Triassic
Adjective
start of the Mesozoic era when dinosaurs first emerged.