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What you will learn from this videoWhat you will learn
- Human anatomy is similar to the anatomy of many other organisms.
- Humans develop from an embryo with a temporary tail.
- Scientists look at fossils to see how the anatomy of organisms has changed over time.
- Discussion Questions
Before Video
What are fossils and what are some examples of fossils? ANSWERFossils are evidence of past life. They can be preserved in different forms like rock, amber, ice, and petrified wood.
Animals become extinct when there are no more left of their species on Earth. After animals are extinct, fossils provide evidence they once existed.
Organisms become extinct for different reasons. Most commonly, they become extinct because they no longer have the ability to acquire the necessary resources (food, water, mates) to survive long enough to reproduce and have more young.
Adaptations are changes in populations of organisms over time. Those changes are a result of some organisms within the population having characteristics that increase the likelihood they will survive to reproductive age. Because of that, those characteristics become more common over time, thus increasing in number in the population.
Changes in the environment will affect many things about how an organism lives, specifically its access to resources. Environmental changes resulting from natural disasters or other occurrences cause certain characteristics to be most favorable for survival.
Populations that do not change over time in response to environmental changes will eventually become extinct. After extinction occurs, the only evidence existing of those previous life forms are fossils. Fossils are examined today in order to determine if prehistoric creatures are similar to more modern ones.
After Video
How are male and female human skeletons the same and different? ANSWERAll bones in males and females are arranged in the same ways, but on average males have slightly wider shoulders and females have slightly wider pelvises.
Dogs, dolphins, bats, and humans all have a similar pattern in their upper arm bone structure—one big bone connected to two bones, connected to many bones, connected to finger-like bones.
Their bones have the same basic pattern, and their skulls connect directly to the spine.
They all start out as a single cell and develop the same pattern of structures such as tails and pharyngeal slits. Some of those structures remain as the embryo gets older, but others go away.
Horses, whales, snakes, birds and more have evolved!
They study how living things grow from a single cell to highly complex organisms.
- Vocabulary
- Comparative anatomy DEFINE
Observing similar structures in organisms and comparing them to each other.
- Organism DEFINE
Any living thing.
- Embryo DEFINE
An unborn or unhatched baby.
- Fossils DEFINE
Preserved organisms from many years ago showing a record of past life.
- Skeletal system DEFINE
A system in organisms made up of bones; organisms can have an exoskeleton (outside the organism) or an endoskeleton (inside the organism).
- Fossil record DEFINE
A collection of fossils over time that shows changes in organisms.
- Limbs DEFINE
Extensions from the trunk or core of an organism (e.g., arms, legs).
- Pharyngeal slits DEFINE
Structures in embryos that will develop into gills in fish and the neck and jaw in humans.
- Evolution DEFINE
Changes in living things over generations.
- Developmental biologist DEFINE
Scientist who studies how living things can grow from a single cell into highly complex organisms.
- Comparative anatomy DEFINE
- Reading Material
- DIY Activity Guide
- Lesson Plan
- Teacher Guide