Evolution

EVOLUTION

What is it? What evidence is there to support it?

Think about itEarth has millions of different kinds of organisms of every imaginable shape, size, and habitat.

The variety of living things is called________________. How did all these different

organisms arise? How are they related?

biological diversity

Evolution Explains the diversity of organisms on Earth It is change over time

NO!

Do organisms evolve?

Populations do

What is the evidence for evolution? Paleontology

What is Paleontology?

Study of Fossils Evidence of living things from long ago

Body fossils Trace fossils

Body Fossils

Ammonite Fern

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Trace Fossils

Tracks Coprolites

What is the evidence for evolution? Paleontology Comparative Anatomy and Physiology

Comparative Anatomy and Physiology Vestigial Structures Transitional Species Homologous Structures

Vestigial Structures

Dogs & Dew claws Eye sockets & Blind Cave fish

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Transitional Species

Archaeopteryx Tiktaalik

Are there any extant organisms that have traits of one group of animals and traits from another?

Something to think about…

Yes!

Behold the Platypus!This animal is classified as a mammal however it has many reptilian traits• Lays eggs• Has a bill• Has a poisonous spur• Sensory organs on bill

similar to that of a crocodile

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Homologous Structures

What is the evidence for evolution? Paleontology Comparative Anatomy and Physiology Embryology and Molecular Biology

Embryology Hypothesis:

If animals share a common ancestry then it will be reflected in their development

Developmental Patterns Homeobox (Hox) genes

are responsible for “telling” the embryo to develop certain features; eyes, arms, wings, legs, fins, etc.

Whale and Dolphin Embryo with…

Hind limbs!

Hind Limbs expressed!

What is the evidence for evolution? Paleontology Comparative Anatomy and Physiology Embryology Biogeography

Biogeography

The distribution of similar plants and animals around the planet suggests that their environments drove the evolution of species that are similar