Biology Chapter 16: Evolution and Natural Selection

Charles Darwin

Father of Evolution

HMS Beagle

The Ship he sailed on for his journey

Artificial selection

The process by which humans choose and breed organisms with specific traits to develop new traits or to help to future enhance the next generations.

Natural selection

Organisms that are best adapted to an environment survive and reproduce more than others.

4 steps of natural selection

Overproduction, Variation, Competition, Selection.

Overproduction

Each species produces more offspring that can survive.

Variation

Each individual has a unique combination of inherited characteristics.

Competition

Individuals compete for limited resources: Food, water, space, mates.

Selection

The individuals with the best traits/adaptations will survive and have the opportunity to pass on their traits to their offspring.

Evolution

The process by which living organisms change over time.

Fossil

A record of the history of life on Earth.

Pangea

All the landmasses on earth were all joined together.

Plate tectonics

The scientific theory that earth's outermost layer is broken into large, rigid plates that slowly move across the planet; this causes earthquakes, volcanoes and mountain ranges.

Law of superposition

States that the younger layer of rock is at the top and the older layer of rock is closer to the Earth's core.

Embryo

A tiny baby that is still developing inside its mother's body.

Embryology

Embryos of all vertebrates are very similar early on.

Fitness

The ability to survive long enough to reproduce.

Adaptation

An inherited trait that increases an organism's chances of survival.

Sedimentary Rocks

Rocks formed from layers of accumulated sediment, like sand, mud, and the remains of dead organisms, that get compacted and cemented together over time.

Metamorphic Rocks

Rocks that have been transformed from existing igneous, sedimentary, or other metamorphic rocks through processes like heat, pressure, and chemical reactions.

Igneous Rocks

Formed from the cooling and solidification of molten rock, either magma within the Earth or lava on the surface.

Types of Adaptation

Camouflage: Fur color blending into the surrounding so that predators can't see them.

Variation importance

Because the environment changes, the more variation within a species, the more likely it is to survive.

Descent with modification

Each living species has descended, with changes, from other species over time.

Common descent

All living organisms are related to each other.

Cladogram

A branching diagram that illustrates the evolutionary relationships between different groups of organisms based on shared traits and characteristics.

Cladistics

A method of hypothesizing relationships among organisms; a method of reconstructing evolutionary trees.

Evidence of Evolution

Fossil Record, Homologous body structures, Analogous Structures, Vestigial structures, Biochemical evidence.

Archaeopteryx

The missing link between reptiles and birds.

Homologous body structures

Similar in anatomy in different types of animals because of a common ancestor.

Analogous Structures

Can be used for the same purpose and can be superficially similar in construction, but are not inherited from a common ancestor.

Vestigial Organs

"Leftover" traces of evolution that serve no purpose.

Biochemistry

DNA with more similar sequences suggest species are more closely related.