Both_______ and ________ show the relationships between organisms, but their main difference is how they compare them. ... The difference is that the length of the lines in a _____________ represents time while the lines in _________ are the same length.
cladograms, phylogenetic trees, phylogenetic tree ,cladograms
Evolution from fish
fish-> tiktaalik-> tetrapods
Earliest in evolution was
fish, have spine, embryos look similar, fish and tetrapods have really close DNA
To find the right fossil...
scientists have to look for the right age of rocks and types that hold fossils
Characters that are similar because of descent from a common ancestor are said to be _______, or a ________ among descendant species
homologous, homology
Similarities due to independent adaptation by different species are said to be _______ or an ________
analogous,, analogy
What we need to build phylogenetic trees are homologies that are shared by some, but not all, of the members of the group under consideration. These shared derived characters are called __________.
synapomorphies,
The presence of lungs provides one piece of evidence that lungfish are the sister group of tetrapods. This approach to building a phylogenetic tree, or phylogenetic reconstruction, on the basis of synapomorphies is called ________.
cladistics,
True phylogeny
: actual way in
which life evolved
-
but _________
�
Phylogenetic reconstructions
provide a
_____________________
available in the present
�
Phylogenetic hypotheses
improve with__________________________
we can't go
back in time to witness it!,
hypothesis
of evolutionary
relationships based on the data,
more data and more
species sampling
Tips of phylogeny
taxons
WHAT we need to make phylogeny
(characters and character states)
:
!
________________data (extant and extinct
organisms)
!
____________________ data (mostly extant organisms)
Morphological , Molecular
Similarities:
between species for creation of phylogeny
Homologous structures (2 bones, 1 bone, many bones, digits)
Embryos look similar
Tiktaalik
transitional fossil between fish and tetrapods
Fossils help us understand diversity through time
1.
Animal _______
has increased
through time
2.
____________has
occurred
constantly
through time
diversity, extinction
Fossils are our ___________to extinct species
�
Fossils help us understand________
only connection , transitions
What was the main question the author addressed? (cycads research)
Diversity. Maybe the dinosaurs had a rule in it. Cycads today=" living fossils" vs more recent diversity? (later diversification event and not the dinosaurs)
What is the rationale for this question? (cycads research)
Cycads use to be common. However, there was a large decline in cycads (why?)
What is the general experimental approach to this research?(cycads research)
Sample cycads for gene and look for and see if cycads had this gene. They also did global radiation by sample them all around the world. And created time tree-> cycad fossil, they were finding them and then on the age of this fossil they will add them to
What does evolution
depend on?
Heritable variation
Hydrangeas growing in two different
environments can affect the flower color
Phenotype is affected by both
Pink______, Blue______
genotype
and
environment
Only source of variation
Mutation
Where does variation come from?
mutation and sexual recombination (reshuffling of existing variation)
Recombination
independent assortment, crossing over, random muting
Allele
An alternative form of a gene.
gene pool
All the genes, including all the different alleles for each gene, that are present in a population at any one time
Evolution is a two step process
1.Variations arise among individuals in a
population
2.Proportions of variant types change from
generation to generation (implies variation
must be inherited)
darwin tree of life
T]he great Tree of Life covers the earth with ever branching and beautiful ramifications
Describe the importance of variation to a population
It is advantageous to a population as it enables few individuals to adapt to the environment changes thus, enabling the survival of the population.
Genetic variation in a population refers to ...
Multiple alleles within a gene pool
Heritable variation is required for evolution; in general,
acquired traits are ___ heritable
not
Evolution is a ________process that depends on _____ variation
two-step , heritable
As species proliferate, their evolutionary relationships unfold in a tree-like pattern, with individual species at the ____tips and their closest relatives connected to them at the nearest fork in the branch, called a _______. Thus, a node represents the
twig , node, recent common
_______ is one of two related disciplines within systematics, the study of evolutionary relationships among organisms. The other is ________, the classification of organisms.
Phylogenetics, taxonomy
Taxonomy order
Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
Phylogeny
The evolutionary history of a species compared by their anatomical and molecular structure. Creating a phylogenetical tree.
A more technical word for "group" is _____
Taxon
Modern taxonomic classifications emphasize groups that are __________________
monophyletic, meaning that all members share a single common ancestor that is not shared with any other species or group of species
The group "reptiles" is ______, meaning that it includes some, but not all, of the descendants of a common ancestor.
paraphyletic
Groupings that do not include the last common ancestor of all members are called __________
polyphyletic.
The nested pattern of similarities among species has been recognized by naturalists for centuries. In the vocabulary of formal classification, closely related species are grouped into a ___________.. Closely related genera, in turn, belong to a larger, mo
genus (plural, genera), family, class,, phylum (plural, phyla), kingdom, domains
Genetic variation has two sources:
mutation and recombination
All the alleles present in all individuals in a species are referred to as the ______ of that species.
gene pool