Biology 100 Unit 13 Flashcards
________________’s influential book entitled On the Origin of Species by Means of Natural Selection was published on November 24,1859.
Charles Darwin
Over generations, individuals with the best functioning traits are consistently selected, _____________ ____________ are produced.
evolutionary adaptations
Darwin’s research was nontraditional because he suggested that ___________________________
the Earth was relatively old and populated by all species being related to each other.
In his theory, he predicted _____________________to have existed between species
numerous intermediates
Darwin’s views were
embraced by some, and rejected by others
In December 1831, Darwin (age 22) left Great Britain as the on board naturalist of the ____________
HMS Beagle.
Darwin realized that the distribution of species in the _________________ was unusual.
galapagos islands
It was apparent to him that many Galápagos species resembled those found in South America, but showed some____________________
variation
Darwin was strongly influenced by the writings of geologist ____________, who promoted the idea of an ancient Earth.
Charles Lyell
What two things was Darwin convinces of
– the Earth was very old, had been shaped by slow processes and continues to change even today.
– just as earth changed, or evolved, so could the organisms that lived upon it, because they responded to their environment
– the Earth was very old, had been shaped by _____
___________, and continues to change even today.
slow processes
just as earth changed, or evolved, so could the organisms that lived upon it, because they
responded to their environment
In The Origin of Species, Darwin emphasized two main points.
– All organisms inhabiting Earth today are derived from ancestral species that may have looked differently (descent with modification).
– The mechanism by which this was accomplished is natural selection
– As organisms reproduce, they can have a variety of offspring. Those offspring best fit for their environment are most fit to survive and reprorduce
What are the 4 evidences used to support evolution
fossils, biogeography, comparative anatomy, and molecular biology
are remnants of organisms that lived in the
past that have been turned to stone.
fossils
fossils can include
plants, animals, impressions, bones, & soft tissues.
______________ is where fossilization is most likely.
sedementary rock
Fossils are often used to
compare anatomy with extinct organisms with extant ones
interpreted as chronology of fossils embedded in rock layers of different ages.
fossil record
Fossil records are used to
show that organisms appeared in a historical sequence.
Older more primitive organisms at the_______
bottum of fossils
________more advanced organisms at the top of the fossil
newer
is the study of the geographic distribution of species.
biogeography
Darwin observed Galápagos birds that resembled those in South America. The resemblance infers that
they shared a common ancestor.
Natural selection then explains that organisms
must have specific characteristics to live in a particular environment
is the comparison of body structure between different species.
comparative anatomy
is the similarity of structures due to common ancestry
homology
Ancestral structures became
modified to undergo a new function
__is the similarity of structures based on function, but does not share common ancestry.
analogy
Forelimbs of mammals are constructed from the same skeletal elements, because they are interpreted as sharing a common ancestor they are considered _____________
homologous structures
is the comparison of structures that appear similar during the development of different organisms
Comparative embryology
During early embryology, some vertebrates look similar, implying they have very similar features, which may indicate ______________________.
common ancestry
is also used to show evolutionary relationships among species.
Molecular biology of organisms
can be used to determine how distantly (or closely) organisms are related.
DNA sequence
The more similar one’s DNA is to an organism,
the more likely that they are closely related
The less similar one’s DNA is to an organism,
they are more likely distantly related.
The similarity between human and chimpanzee DNA is __________.
98%
This is the most similar genetic match of humans with any species.
The similarity between human and chimpanzee DNA
Evolutionary biologists indicate that the genetic match of humans with any species. is due to
a close evolutionary relationship.
Darwin’s Galápagos ————re an example of adaptive evolution as a result of natural selection.
s finches a