What is a skeleton? A skeleton consists of the bones that make up the framework of a body.
Exercise directions In this exercise, we will be looking at the form and function of different skeletons and how they suit the lifestyle of those animals. Let’s try a few examples.
observations Making Observations: Take a few minutes to make some observations about the form of this animal.
example For example, you might say…. Short arms with finger-like appendages Long, thick-boned tail that reaches to the ground Elongated rear limbs with shorter bones connecting them to the pelvis. Large feet
inferences Making Inferences: To make an inference means to draw conclusions from your observations. What are some functions of these structures??
Some questions you might start with are… What are the arms used for? Why is the tail so long and sturdy? How might long, skinny legs help it move? Why are the feet so large?
How does form relate to function? Click on a part of the animal to find out
An adaptationis a characteristic that helps an organism survive and reproduce in its environment. Can you identify a structure that serves as an adaptation for a kangaroo?
Observations: • Hoofed feet • Thing, long legs • Long neck • Short, skinny tail
Observations: • -Thick beak • Elongated, skinny legs • Three skinny toes • Long, tapered neck
Click on parts of each animal to learn about their adaptations.
How do the similar structures of these two animals serve as different adaptations to their environments?
Observations: • Long tail • Small skull • Short limbs • Five toes per foot • Body set low to the ground
Observations: • Elongated torso • Short limbs • Small skull • Body set low to the ground • Front feet larger than back feet • Five toes
Gila Monster Iguana
Click on a part of the animal to learn about these adaptations.. Gila Monster Iguana
How do these structures have similar and different adaptations?
A homologous structure is a characteristic shared by related species that has been inherited from a common ancestor. See example
In this next example, take note of any homologous structures that could support an ancestral link between these two animals.
Observations: • Small skull with sharp teeth. • Forelimbs proportional to rear limbs. • - Long tail • - Four paws with claws.
Observations: - Large skull with protruding fangs. - Prominent front and rear claws. - Broad shoulder blades - Dense forelimbs - Long tail
Cats and Lions are closely related species, therefore, they exhibit structures called “homologous structures”
Can you identify some homologous structures between cats and lions?
Analogous structures are two structures with the same function but no evolutionary link. See example
Observations: • Hard, outer shell • Small skull • No visible teeth • Four toes • Thin forelimbs and back limbs