Biological Evolution

mutation

A change in a gene or chromosome.

Phylogenetic

A family tree that shows the evolutionary relationships thought to exist among groups of organisms

species

A group of similar organisms that can breed and produce fertile offspring.

gene pool

All the genes in a population at any one time

adaptation

An inherited trait that improves an individual's ability to survive and reproduce in a particular environment.

According to the fossil record found in these sedimentary layers, what conclusion can be drawn about the movement of life to land?

As land plants became more complex, animal life did as well.

The Earth formed over 4.6 billion years ago.The Geologic Time Scale pictured above represents the timeline of historical events that have occurred since Earth formed. "The Cambrian explosion was the relatively short evolutionary event, beginning around 544 millions years ago In the Cambrian period and ending in the Cenozolc era, during which most major animal phyla appeared, as Indicated by the fossil record. Which time period during the Cambrian Explosion Introduced the most variation In DNA sequences?

Devonian

cladogram

Diagram that shows the evolutionary relationships among a group of organisms

alleles

Different forms of a gene

A team of archaeologists excavating a sedimentary rock layer come across some primitive hunting tools used by early humans. As the dig progresses, they unearth the fossilized remains of a dinosaur from another layer of the sedimentary rock. Why do these discoveries indicate that the rocks were formed over millions of years?

Dinosaurs became extinct millions of years before humans appeared.

explain which fossil the geologist should use to compare the rock layer to other layers and estimate when the layers were deposited?

Fossil X, because the fossil has unique features and Is only found in a few locations.

timeline of events that explains the formation of the rock layers in the diagram?

Layers R—T formed —¥ Layer T eroded —^ tectonic pressure pushed layers at an angle —> Layers U—Z formed

A group of students was hiking along a riverbank in Louisiana and found a fossil of a shell in the gravel. One student identified the shelled organism as an organism that once lived on the seafloor. Explain how the shelled organism fossil formed over time?

Louisiana area must have once been covered by the sea and that the fossil formed over millions of years.

Based on the information in the chart, during which eon would you expect to find fossil evidence about the evolution of insects?

Phanerozoic

natural selection

Process by which organism that have better adaptations (inherited traits) to their environment survive and reproduce most successfully; also called survival of the fittest

The information in the diagram BEST supports which hypothesis?

The fossil in layer C is older than the fossil in layer D.

Fossils are the preserved remains of previously living organisms or their traces, dating from the distant past. Unfortunately, the fossil record is not complete or unbroken because most organisms never fossilize, and even the organisms that do fossilize are rarely found by humans. Fossils are often contained in rocks that build up In layers called strata. The strata provide a sort of timeline by which scientists can date fossils. Fossils offer unique and valuable insights into evolution over long periods of time. Which statement can best be inferred from the fossils pictured here?

The oldest fossils are found in the deeper layers and the youngest near the surface.

Which Statement about the numbers of different types of organisms Is not supported by the data In the graph?

The overall amount of organism diversity has decreased overtime.

What evidence best supports the claim "time period during the Cambrian Explosion Introduced the most variation In DNA sequences?"

There is more physiological differences in the organisms introduced during this time period

Offspring

a new organism that is the product of reproduction

Rock strata allow geologists to perform relative dating. What are some essential things that relative dating includes?

determining a sequence of events and determining what order events occur in

What can be deduced from analyzing rock strata?

extinction of a species evolution of a species climate volcanic activity

evidences of common ancestry

fossil records, biogeography, embryology and homologies (anatomical, molecular, and developmental)

correctly list the sequence and relationship between volcanic eruptions and igneous rock and metamorphic rock.

igneous rock, sedimentary rock, metamorphic rock, magma

terrestrial

of, on, or relating to the earth

Scientists discovered fossils in several layers of the Earth you see here. They found fossils of algae, snails, and clams in layer D. Given that information, where do you think they found fossil evidence of simple land plants and amphibians?

point F

fossil record

preserved remains or traces of organisms; remains found in lower layers of rock are older

anatomical homology

similar structures but different functions

biogeography

similarities due to location and time

molecular homology

similarities in DNA or amino acids

Embryology

similarities in embryo development or growth

Due to a rise in global sea level, a shallow sea covered most of eastern Virginia during the Cretaceous. Virginia had drifted north from the equator and conditions no longer supported the formation of limestone. The tropical climate disappeared, replaced by more temperate conditions. In place of sediments, sand and silt were deposited as the sea level receded in the region we now know as the Plateau region. Under these conditions, we would expect to find more fossils of life forms in this location.

terrestrial

What can scientists infer about a specific period of Earth's history if many fossils were discovered from oxygen-breathing organisms?

the atmosphere had lots of oxygen

What can scientists infer about the observation of the fossils now found widely spaced across the globe that actually lived on the same early Earth landmass?

the landmass split apart

A fossil is...

the preserved remains or traces of animals, plants, and other organisms from the remote past.

gradualism

theory in evolution where organisms will gradually change over time

Scientists have studied the fossilized shells of prehistoric, single-celled marine organisms. Some of these shells were thin, which indicates that the organisms lived In very warm ocean water. Such evidence indicates that the climate during this time may have been

tropical

Common ancestor

two species that have a lot in common most likely evolved from a...

inherited variation

variation in the parent genes being passed down through genetics; versions of a gene that work best in an environment is more likely to be passed down to the next generation of offsprings