Download Guided Notes - Leon County Schools

Biological Evidence of Evolution
 The degree to which species are ________________depends on how closely in
time they ________________, or split, from their common ________________.
 Evidence for Evolution comes from 6 areas
1. Fossils
a. Although the fossil record is incomplete, it contains many examples of fossil
sequences showing close ________________ ________________.
b. The fossil record indicates that different ________________ of similar
organisms often ________________ with each other.
 Comparative anatomy is the study of ________________ and ________________
among ________________ of living species.
 By comparing ________________of different species, scientists are able to find
________________ as to how organisms are________________.
2. Homologous Structures
a. Homologous structures are body parts of organisms that are similar in
________________ and ________________ but different in
________________.
b. The ________________ of these species are different sizes, but their
________________ and ________________ suggest common ancestry.
3. Analogous Structures
a. Body parts that perform a similar ________________ but differ
in ________________ are analogous structures.
b. These structures developed ________________ of one another. They are
made of different ________________ and have different
________________, however, both ________________.
c. These organisms did not have a common ________________with wings, but
both developed wings over time.
d. It illustrates that organisms can ________________ over time.
4. Vestigial Structures
a. Vestigial structures are body parts that have ________________ their
original ________________ through evolution.
b. The presence of these structures suggest that they once ________________
them, but have changed so they no longer need them. If they did not need
these structures at one point in their evolutionary ________________, then
why have them?
5. Embryology
a. The science of the development of ________________ from fertilization to
birth is called embryology.
b. The remarkable ________________ among with similar ________________
that not all exhibit as adults suggests they once had a common
________________.
6. DNA
a. Molecular biology is the study of ________________ structure and function.
b. Discoveries in ________________ ________________have confirmed and
extended much of the data already collected about the theory of evolution.
c. Scientists can study relatedness of organisms by comparing
________________ and proteins among living species.
d. Scientists have found that some ________________ of shared DNA
________________ at regular, predictable rates.
e. Scientists use this “molecular clock” to ________________ at what time in
the past living species ________________ from common ancestors.
f. Molecular data indicate that whales and porpoises are more closely related to
________________ than they are to any other living species.
 New evidence supporting the theory of evolution by natural selection is discovered
nearly _______ ___________, but scientists debate some of the
________________.
 New ________________that have features of species that lived both before them
and after them help scientists study more details about the origin of new species.
 Many scientists think that natural selection produces new species
________________ and ________________.
 Other scientists think species exist stably for long periods, and change occurs in
short ________________.