Vocabulary
The trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock.
Fossil
What type of fossil is formed after an organism's tissues decompose, and an impression of its body shape is left in sediment. Then water seeps in and fills the impression, and the minerals in the water then harden to form this type of fossil.
Cast and Mold Fossils
What types of organisms lived in the Pre-Cambrain Era?
Single-celled life
The process of biological change by which populations become different from their ancestors over many generations.
Evolution
What type of rock do scientists use radiometric dating on?
Igneous rock
The death of every member of a species
extinction
Finish this sentence: The rock layer on top is _______________ because it was deposited most _____________. The rock layer on the bottom is ________________ because it was deposited the _____________.
newer/youngest, recently, older/oldest, earliest
What happened in the Cambrian explosion?
A large increase in the variety of animals/fossils found, and many animals with hard outer shells/ predators.
Are dinosaurs and birds related? Explain using anatomy
Yes because new fossils show that dinosaur fossils have similar structures as modern bird feathers.
How do scientists infer that a mass extinction occurred?
They can infer that a mass extinction occurred when large numbers of species disappear from the fossil record.
The idea that organisms share a common ancestor at some point in the past; that all living organisms and all fossil organisms can be traced back to one or a few ancestor organisms or cells.
Common ancestry
What is an ordered arrangement of rock layers that is based on the relative ages of rocks called?
Geologic column
What new features did the multicellular organisms have after the Cambrian explosion?
Features like, feet, lungs, hard shells, jaws all show increasing complexity and change in organisms.
Fill in the blanks: Genetic information in the form of ____________, gets passed from generation to generations. Because of this, offspring look ______________ their parents. Overtime, genetic changes add up. Populations come to look more and more _____________ their ancestors.
DNA, Similar to, different from.
Describe the method of analyzing relative ages of rock layers.
Compare different locations with similar rock layers.
The study of the development of an animal from the fertilized egg to the newly born or hatched organism.
Embryology
Scientists use the change or decay of unstable particles, that make up matter in rocks and living organisms to determine ___________
Absolute Ages of Rock Layers
What happens after a mass extinction?
Periods of rapid growth in Earth's biodiversity.
What do similarities in anatomy indicate? What is an exception?
Similarities in anatomy can indicate evolutionary relationships or common ancestry, but function of the similarity also plays a roll in determining common ancestry.
Scientists use fossil data to estimate the number of species for each plant type of time. Explain how they estimate the ages of plant fossils found in different rock layers.
Scientists can measure absolute dates of some igneous rock layers, and use relative dating to infer the age of rock layers where fossils are found. Fossils found in lower rock layers are older than the ones in layers above.
A method of determining the absolute age of an object by comparing the relative percentages or ratio of a radioactive (parent) substance and the stable (daughter) substance found in the object.
Radiometric Dating
Comparing the amount of unstable radioactive particles to stable particles allows scientists to find ___________________?
Radiometric Dating
What are transitional fossils?
Fossils of organisms that have body structures that are found both in an ancestral specials and in its descendants.
How does embryology help scientists to determine similarities in organisms?
Scientists study the growth and development in unborn or unhatched organisms, this allows them to look for patterns and structures in organisms and then determine if they have a common ancestor.
Explain how inferences about evolutionary relationships can change as new evidence is discovered?
New information or discoveries may clarify questions or assumptions that scientists have about extinct organisms. New information may also prove a hypothesis or theory to be false.