Teaching in the Exhibition
The Extreme Mammals exhibition uses fossils, models, live animals, interactives, videos, and more to engage individuals with all learning styles. This guide divides the exhibition into ten areas, which are indicated on the map and described below. For answers to the Guiding Questions below, click here
Living and fossil mammals exhibit a huge range of shapes and sizes.
- Animal models: Have students compare and contrast these life-size models of the largest land mammal and the smallest mammal that have ever lived. Point out that despite all the differences, we're all mammals.
- What do the largest and the smallest mammals have in common with each other? With humans?
2. What is a Mammal?
Mammals are defined by common ancestry, not by physical characteristics—although inherited traits do help us recognize relationships between mammals.
This opening on the skull of synapsids, like Cynognathus and mammals, show that they are related.
- Video: Encourage your students to watch the video, focusing on the traits shared by living mammals.
- Skulls: These show how specialized teeth and skull anatomy evolved in the ancestors of mammals. Ask students to compare the skulls and how they've changed over millions of years.
- Cladogram: The wall-size evolutionary tree shows where mammals fit in the tree of life and how all mammals have evolved from a common ancestor. Point out the many branches. Ask students what this shows about mammal evolution.
- Most living mammals have certain traits in common. Why? What are they?
- How do scientists determine what a mammal is?
3. What is Extreme?
"Extreme" traits differ widely from those found in ancestors, or from the most common, typical, or "normal" form at any moment in time. Most mammals possess a combination of extreme and normal features.
- Human, Uintatherium, and opossum skeletons: Ask students to distinguish between normal and extreme characteristics in each of these species.
- What are some examples of extreme and normal characteristics in these three mammals?
- Are humans extreme or normal? Why?
4. Head to Tail: Heads
Mammalian bodies have been modified by evolution. Some of these changes are found in the head.
- "Headgear" and skulls of living and extinct mammals: Point out to students that headgear can be formed from teeth, bones, and even hair. Ask them how horns and antlers are similar, and different.
- Skulls with teeth: Invite students to compare and contrast the different types of mammal teeth, and to use the mirror to compare them to their own teeth.
- What are different kinds of teeth used for?
- What are some of the functions of headgear?
5. Head to Tail: Reproduction
Reproduction is one of the main features that differentiates the three living groups of mammals: placentals, marsupials, and monotremes. (See "Useful Concepts.")
- Taxidermy and fossil specimens: Invite students to examine these specimens, as well as the video, and explore how each of these groups gives birth.
- How do different types of mammalian mothers care for their young?
- How do the gestation periods for each of the three major groups compare? What are some of the benefits of a long pregnancy? The drawbacks?
6. Head to Tail: Bodies
Live animals! Ask students to describe how sugar gliders move and interact.
All mammals share a common body plan, but evolution has resulted in astonishing variations on the arrangement of bones, muscles, and skin.
- Glyptodont armor: Students can "try on" the model and imagine having this much armor. Ask how it might compare to having spines or scales.
- Hair and fur: Point out that hair, horns, scales, hooves, and fingernails are all made of the same material, keratin. Invite students to touch and explore the specimens.
- What are the various functions of hair and fur?
- How do different body coverings benefit mammals? How do these coverings relate to environmental conditions?
- Which would you rather have, venom or armor? Why?
7. Mammals in Motion
Ancestral mammals lived on land. Some groups of mammals later adapted to move through
other environments like the sky and the ocean.
Ambulocetus, an amphibious early whale with legs, probably hunted small mammals much as today's crocodiles do.
- Walking whale model: Explain that like most other mammals, all whales are descended from an ancestor with four limbs and feet. Ask students whether Ambulocetus lived in water or on land, and to support their answers.
- "Lucy" pelvis: Look closely at the diagram comparing "Lucy's" pelvis with those of chimpanzees and humans. Ask students how these mammals moved, and how human locomotion is unique.
- Bats, flying squirrel, and Mesozoic gliding mammal: Have students note the similarities between the bat wing and their own arm. Ask them to compare bat flight to the gliding of the squirrel or the Mesozoic mammal (Volaticotherium).
- How do most mammal bipeds (those that walk on two legs) get around?
- Many groups of mammals evolved to live in water. How did their bodies change?
8. Extreme Climates
Environments change with time, and so do the mammals that inhabit them.
- Diorama of the Eocene and Images of Today: Ask students to compare conditions on Ellesmere Island 50 million years ago to those today.
- How are the mammals in each scene adapted to their environment?
- What are some of the ways in which major climate change has affected mammal diversity?
9. Extreme Isolation
When mammals are geographically isolated, they can evolve extreme traits or can come to resemble unrelated species elsewhere. (See "Useful Concepts.")
- Monkey skull: Have students read the displays, and ask them to explain how the skull solved the puzzle of how and when monkeys reached South America.
- Scarrittia case: Point out that these South American species all belong to the same group, and resemble a wide range of groups found on other continents.
- What kinds of extreme forms have evolved in places that once were isolated?
- Why is isolation so important in the origin of different, distinctive, and "extreme" forms?
10. Extreme Extinction
Although sometimes rapid, and affecting vast numbers of species, extinctions are part of the
history of life. One mammal, Homo sapiens
, is contributing to what may become the next mass extinction (the "Sixth Extinction").
- La Brea Tar Pits walk-through display: These mammals are only 11,000 years old, but all are extinct. What does this tell us about how fast extinction can occur? How does it affect species diversity?
- Tasmanian wolf specimen: Ask students to think about what is unusual about this marsupial.
- What human activities contribute to extinction?
- How can preserving existing habitats slow extinction rates and lead to the discovery of new species?