Unit 1.1 Flashcards
Ecology def
the study of the interactions and relationships among organisms and their abiotic environments.
evolution def
development or change of species over time resulting in differences among organisms
why do we study eco and evo together
because together they provide the framework to study and understand life on earth
Darwins popular book
ORgin of Species
Descent with modification 3 big factors
new species are produced from old species
new species are distinctly different from old species
all species evolved from a common ancestor
thomas malthus was a what
an economist
what did malthus say
the the exponential rate of human population growth is greater than the rate of increased food supply. if unchecked, famine will occur
those with favorable variatons or who can better acquire resources can…….
survive while others do not.
NATURAL SELECTION is what processe
ecological processes are driving evolution
what does it mean that adaptations to the envrionment result from organisms of different genotypes in a population contributing differently to the gene pool of succeeding generations
natual selection
how does natural selection relate to inheritable traits
organisms inherit traits that increase their finess relative to others.
Adaptation def
a characteristic trait that enables an organism to survive and/or reproduce in a particular place and time
survive and reproduce is a way for what
an organism to pass on their genes/traits
FITNESS is what in depth
a meausre of reproductive success determined by the contribution made to future generations
FITNESS simple
survival and reproduction
the more you contribute, the _____ your fitness
higher
Are all traits either selected for, or against, by the environment.
No, not all
there are ____ many points for understnading evolution via natural selection
4
1st point to understnad evolution ….
there are differences between individuals in the same species
2nd point to understand evolution…
characteristics can be inherited
3rd point to understand evolution….
the environment will have different effects on individuals with different phenotypes
4th point to understand evolution….
some genotypes and their phenotypes are more likely selected by the environment, while others are more likely selected against
TOLERANCE def
in ecology, tolerance refers to the idea that organisms live within a range of too much and too little
an organisms ability to _____ certain ______ conditions, will determine its _______ success, _____, and ability to ______
tolerate, environmental, reproductive, growth, survive
Tolerance curve x and y axis
x axis is environmental conditions and y axis is the response of species
Regions of tolerance curve
zone of intolerance, then lower limit, then section of survival, then growth, then GREATEST FITNESS in center, then growth, survival, the upper limit, and then a zone of intolerance
is the range of tolderance fixed ?
no
why isnt tolerance fixed ?
the environment is never constant. so an organisms range of tolerance is likely to change accordingly.
Population def
a group of a given species at any scale
community def
multiple populations in a given place
ecosystem def
living and nonliving together. community and environment. biotic and abiotic
environment
the factors in which an organism interacts with
phenotype
the physical trait. outward expression
genotype
the genetic material , its what causes phenotypes
species
organisms that can sexually reproduce and produce fertile offspring
a populations or species range of tolerance can be linked to what
the range of phenotypes expressed at any given time
in general, max fitness is obtained by what
phenotypes that are best suited for the intermediate portion of the environment
Modes of selection types
directional selection and stabilizing selection and disruptive
directional selection def
sometimes there may be a tendency for the phenotypes in a population or species to shift toward one extreme OR the other
ex of WHY directional selection
the environment might change and there are differences among the individuals
stabilizing selection def
sometimes there will be a tendency for the phenotypes in population or species to become constrained around the intermediate area of max fitness
ex of WHY stabilizing selection
they lose the extremes. and the environment isnt really changing.
or ex 2 is that the only place to survive is the middle because the extremes are so intense
Disruptive Selection def
when there might be a tendency for the phenotypes to shift to both Extremes. A bi-modal range
ex of why disruptive selection
a new illness goes for the most abundant phenotype to affect the most
