Module 3 Darwin Evolution Flashcards
Gradual change at the genetic level of populations over the course of several generations
Evolution
Occurs when new species arise from common ancestors via descent with modification
Speciation
These guide biological research of today
Charles Darwin’s theory of evolution and chromosomal theory of inheritance
True or False: Early Roman philosophers recognized fossils as evidence for extinct life
False: Greek
True or False: Evolutionary thinking was considered rebellious for most of history
True
Jean-Baptiste Lamarck proposed evolution through ________
Inheritance of acquired characteristics
What theory states that organisms acquire adaptations and pass them onto their offspring
Inheritance of acquired characteristics
Lamarckism is ______
Transformational
True or False: Transformational in Lamarckism refers to the idea that organisms can transform their characteristics through the use and disuse of body parts.
True
True or False: Traits acquired by an organism throughout its life cannot be passed onto offspring
True
Who established the principle of uniformitarianism
Charles Lyell
This principle states that laws of chemistry and physics have not changed throughout the Earth’s history
Principle of Uniformitarianism
According to the principle of uniformitarianism, past geological events that occurred by natural processes are similar to those that are occurring today
True
Why did Lyell conclude that the Earth’s age must be in measured in hundreds of millions of years?
Because rates of sedimentation are
too slow to produce the
layers of sedimentary rock
over a short period of time
True or False: Darwin joined the 5-year voyage
of the HMS Beagle
True
What places did Darwin observe on the similarities
between the plants and animals?
Galapagos Islands and
mainland South America
True or False: Each island in the Galapagos
often had a unique species that
resembled species on the other
islands
True
What did Darwin conclude?
Darwin concluded that
Galapagos organisms originated
from continental South America
and then underwent
modification in the islands
Darwinian evolution is
composed of 5 theories:
Perpetual change
Common descent
Multiplication of species
Gradualism
Natural selection
The living world is neither
constant nor perpetually cycling,
but is always changing
Perpetual Change
True or False: Hereditary continuity is
observed from past to
present life
True
__________ shows the
hereditary continuity
throughout the history of life
Fossil Record
What do fossil show other than hereditary continuity?
Environmental changes
The Trends in fossil diversity are
produced by ___________
Varying rates of species formation vs extinction over time
True or False: All organisms share a common ancestor
True
The last universal common
ancestor likely existed over ______________
4 billion years ago
________ is the evolutionary
history of organisms
Phylogeny
__________ are characters or
character states that share the
same evolutionary origin
Homologies
This show common descent
Homologies
True or False: Homologies were inherited
from a corresponding
character of an ancestor
with some modifications
True
A ___________ of groups
within groups supports a history
of phylogenetic bracketing
Nested hierarchy
Species cluster into groups
within groups based on
suites of similar homologies
Nested hierarchy
________ is the development of
an organism through its entire
life
Ontogeny
True or False: Ontogeny recapitulates
phylogeny
True
True or False: Early developmental features are more widely shared across taxa compared to later ones
True
Which explain the emergence of new homologies?
Changes in the timing of
developmental events and
physical location of structures in
the body plan
_________ is the change in
timing of developmental events
Heterochrony
_________ is the change in
physical location of a
developmental process
Heterotopy
_____ provides the material
from which new species arise
Genetic variation
_________ is the formation
of new species from an
existing species
Speciation
True or False: There is no definitive consensus on what a species is
True (Multiple species concepts
exist)
This states that a species is a
reproductive community of
populations occupying a specific
niche
Biological species concept
________ are biological features that prevent
interbreeding between species
Reproductive barriers (Can be prezygotic (impair
fertilization) or postzygotic
(impair development,
survival, or reproductive
capability)
True or False: Geographic isolation
followed by divergence
can lead to evolution of
reproductive barriers
True
________ are populations of one species
occupying separate geographic
areas
Allopatric populations
True or False: Species cannot interbreed
because of geographic
separation, but can if the
barriers are removed
True
_________ occurs when the separated populations
evolve independently and
develop reproductive barriers
Allopatric speciation
Populations can be separated by
2 means:
Vicariance and Founder Event
The geological or
climate change separates
populations
Vicariance
Small number of individuals
disperse to a distant region
with no members of that
species
Founder event
occurs when individuals within a
species specialize to occupy
different niches within the same
habitat
Sympatric speciation
Example of Sympatric speciation
Cichlid fish in the
African Great Lakes
_______ is the evolution of several ecologically
diverse species from a common
ancestor
Adaptive radiation
True or false: In adaptive radiation, many different species can arise within a short period of geological time
True
Adaptive radiation can be seen in?
It can can be seen
in lakes and young islands
True or False: Volcanic islands initially lack life but are slowly colonized
True (Ex. Galapagos fifinches)
Large phenotypic differences between species only occur through the accumulation of smaller changes over time
Gradualism
This states that new traits are established in a population by increasing their frequency
Populational gradualism
This states that new traits are produced over small incremental changes over hundreds to thousands of generations
Phenotypic gradualism
True or False: Phenotypic gradualism is controversial
True
True or False: Not all changes in phenotype are small
True (Ex. Dwarfifing in dogs and sheep)
_________ states that phenotypic evolution is concentrated in short events of branching speciation followed by longer intervals of morphological stability
Punctuated equilibrium
True or False: Both punctuated and gradual evolution are seen in the fossil record
True
The major process by which evolution occurs in Darwin’s theory
Natural Selection
Explains the origin of adaptation
Natural Selection
True or False: Darwin developed the theory of natural selection based on 5 observations and 3 inferences he drew from them
True
What inference or observation states that all populations produce large numbers of gametes and offspring each generation. Population increases exponentially
Observation 1 - Organisms have great potential fertility
What inference or observation states natural populations fluctuate in size across generations and sometimes go extinct. No natural populations show continued exponential growth.
Observation 2 - Natural populations mostly remain constant in size
In observation 2, no natural populations show continued exponential growth.
True
What inference or observation states that exponential growth of a natural population would require unlimited resources to provide food and habitat. Resources are finite
Observation 3 - Natural resources are limited
What inference or observation states that no two individuals are exactly the same even within population
Observation 4 - Populations show variation among organisms
What inference or observation states that offspring resemble their parents.
Observation 5 - Some variation is heritable
In observation 5, Darwin at the time did not understand the mechanisms of inheritance
True
Which inference or observation states that overpopulation leads to more severe struggles for food, space, and shelter. Only a small part of individuals survive each generation.
Inference 1 - Members of a population undergo a continuing struggle to exist
Which inference or observation states that traits that confer an advantage to survival allow organisms to live longer and pass those traits onto their offspring
Inference 2 - Varying organisms show differential survival and reproduction favoring advantageous traits
Which inference or observation states that propagation of favorable traits transforms species. Natural selection leads to speciation
Inference 3 - Over many generations, natural selection generates new adaptations and new species
In survival of the fittest, it does not mean survival of the physically strongest individuals
True
If survival of the fittest does not mean survival of the physically strongest individuals, then what?
Fitness refers to the ability of an organism to survive to reproductive age and produce offspring
The fitness of an organism depends on?
on its suitability to its environment
True or False: Fitness is not absolute. The “fittest” now could go extinct later
True
Peppered moth (Biston betularia) has two color variants which are?
f. typica (white) and f. carbonaria (black)
Which is more common during pre-industrial England?
White morph (f. typica)
What became more common during the Industrial Revolution?
Black morph (f. carbonaria)
Natural selection is a 2 step process with a random and nonrandom component. Which is the random?
Mutation is random
Natural selection is a 2 step process with a random and nonrandom component. Which is the non-random?
Survival of different traits
This is the ultimate source of new genetic variation
Mutations
True or False: Mutations are chemicophysical changes that affect the sequence of nucleotides in DNA
True
True or False: Mutations can be passed on
True
True or False: Mutations does not prefer advantageous traits
True
_________ is the differential survival and reproduction among varying organisms
Sorting
This can even produce sorting
Random processes
True or False: When natural selection occurs, sorting occurs due to advantageous traits
True
Specific cause of sorting
Selection
