Download Evolution

10.1 Early Ideas About Evolution
Early scientists proposed ideas about evolution.
Evolution
is the biological
change process by which
descendants come to differ
from their ancestors.
A species is a group of
organisms that can reproduce
and have fertile offspring.
There were many important naturalists in the 18th
century.
Linnaeus:
classification system from kingdom to
species
Buffon: species shared ancestors rather than
arising separately
E. Darwin: more-complex forms developed from
less complex forms
Lamarck: environmental change leads to use or
disuse of a structure
Theories of geologic change set the stage for
Darwin’ s theory.
There
were three theories of geologic change. p300
catastrophism
gradualism
uniformitarianism
Uniformitarianism
is the prevailing theory
of geologic change. (key to the past)
10.4 Evidence of Evolution
Evidence for evolution in Darwin’s time came from
several sources.
Fossils
in older layers are more primitive than those in the
upper layers.
 The
study of geography provides evidence of evolution.
island species most closely resemble nearest mainland species
populations can show variation from one island to another
 Biogeography
– the study of the distribution
of organisms around the
world
Embryology
identical
similar
provides evidence of evolution. p311
larvae, different adult body forms
embryos, diverse organisms
Embryology
"the unborn, embryo“ is the branch of
biology that studies the development of gametes (sex
cells), fertilization, and development of embryos and
fetuses.
The
study of anatomy provides evidence of evolution.
p312
Homologous
structures are similar in structure but
different in function.
Analogous
structures have different
structure, similar function.
Analogous
structures are not evidence
of a common ancestor.
Structural patterns are clues to the history of a species.
Vestigial
structures are remnants of organs or
structures that had a function in an early
ancestor.
 Ostrich
wings are examples of vestigial structures.
10.5 Evolutionary Biology Today
Fossils provide a record of evolution.
Paleontology
is the study of fossils or
extinct organisms.
Molecular and genetic evidence support fossil
and anatomical evidence.
 DNA
 Two
Sequence Analysis
closely-related organisms will have similar DNA sequences.
Pseudogene
sequences
providing evidence of evolution.
no longer function
carried along with functional DNA
can be clues to a common ancestor
Homeobox
genes
indicate a very distant
common ancestor.
Protein
Comparisons
Molecular
Cells
fingerprinting
from different species that
have the same proteins most likely
have common ancestors.
Evolution unites all fields of biology
Scientist
from any fields contribute to
the understanding of evolution.
The
basic principles of evolution are
used in many scientific fields.