Ashley
Define the term “biodiversity”
The variety and diversity of species as well as the genetic differences between organisms of a species that exist in an ecosystem
Define the term “evolution"
The change in frequency of alleles (which determine traits) in populations that make them more suitable in their environment
Explain the genetic background of evolution (pool génique)
The genetic background (or gene pool) includes the variety of alleles responsible for traits in the genome of a species
Why is evolution a term designated to describe a population and not individuals?
Explain the connection between evolution and biodiversity
Evolution led to the development of new species (speciation), which we can see today with the vast diversity of species that exists on the planet (biodiversity
Why is evolution a theory and not a law?
Evolution is a theory because a theory attempts to explain how a phenomenon works. Evolution is a fact and is supported with several evidences and experiments. For example, there are mathematical formulas that allow you to calculate the variation in allele frequency in a population . The exact mechanisms underlying evolution continue to be improved and better understood
James Hutton et Charles Lyell:
Study the forces of: 1) wind, 2) volcanoes, 3) water, 4) earthquakes These are capable of transforming the earth and that the earth is very old (older than we thought
Erasmus Darwin:
Competition between individuals = transformations/changes
Jean Baptiste Lamarck
Organisms evolve traits in their lives through their use and these traits are then passed from generation to generation.
Thomas Malthus :
Studies populations and proposes the idea of biotic capacity (a population reaches a limit that the environment's resources can support).
Charles Darwin:
Proposes the theory of evolution by natural selection.
Alfred Russell Wallace:
Comes to the same conclusions as Darwin regarding evolution by natural selection. Consult Darwin
Define the term “adaptation
A change in the organism that increases its chances of reproducing and surviving . Examples: structural, physiological, behavioral changes, etc.
Structural adaptation
Understand the shape/arrangement of the physical characteristics of a environment. organizations. Ex: Hibernation of a bear. Ex: resistant bacteria, body. Ex : the needles on a cactus
Physiological adaptation
Variations in the metabolic processes of organizations.
Ex: resistant bacteria, snake venom
Behavioral adaptation
The way organisms respond to their , environment.
Ex: Hibernation of a bear.
MIMICRY
A structural change/modification in a species. This change makes it look like another, more powerful species that scares away its predators.
CAMOUFLAGE
A structural change/modification in a species. The species is able to “blend” with its environment to hide from its predators.
Why would the most common fur color of a population of mice change with the weather?
the environment changes, mice with the color that gives them the ability to camouflage themselves in their new environment will have a greater chance of surviving, reproducing and passing on the gene for this advantageous color to mice of future generations. Over time, more and more mice will have the advantageous color
Differentiate between the terms “adaptation” and “acclimatization
Acclimatization: the organism becomes accustomed to the conditions of its environment. No changes at the genetic level are made. Adaptation: a structure or physiological character or behavior that allows it to better survive in its environment
. Define, in simple terms, “survival of the fittest.”
Some individuals have beneficial mutations depending on their specific environment. These changes increase the chances of surviving and reproducing, therefore they are inherited by future generations and their frequency in the population increases
Using your knowledge of adaptations, explain in your own words the quote to Darwin: "It is not the strongest of the species that survive, nor the most intelligent, but the one most responsive to change." Use an example to support your explanation.
The quote explains that changing environments (e.g. drought, flooding, etc.) can present challenges for organisms. The organism that can respond best to these changes (due to beneficial adaptation) will have the best chance of surviving to pass that trait on to the next generation. Over time this could cause so many changes that speciation could take place.
List in your own words the two main ideas of Darwin's theory of evolution
a) Current life forms come from a modified ancestral species. b) The mechanism of this modification is natural selection which occurs continuously over long periods of time.
Define, in simple terms, natural selection
The fittest organisms (best adapted to their environment) survive, reproduce, and pass on their fit genes to next generations. The environment ‘decides’ who is fit
Define, in your own words, the following terms: a) overproduction:
The birth rate exceeds the death rate, which means that resources are limited and lacking for certain individuals. The biotic capacity is exceeded
competition:
Limited resources mean that individuals of a species (or species among themselves) must compete (passively or actively) for the same resources
variation
Each individual within the same species is different due to a different genetic code - therefore unique. Some have more different characteristics than others
adaptation
A change in an organism that increases its chances of survival and/or reproduction
natural selection
Changes in characteristics that increase the chances of surviving and reproducing are favored and transmitted from generation to generation.
species differentiation
The “original” species (ancestors) change/undergo modifications which, as a result, create new species. Is called speciation
How did the flora and fauna differ from England and the Galapagos Islands (there are at least four) according to Darwin
Ostriches from Africa and South America had a lot in common but were different species Differentiation in turtles → giant turtles. Differentiation in finches. ⚫Presence of armadillas and sloths.
How did fossils play a role in Darwin’s theory of evolution?
He found fossils of a glyptodon and a megatherium that were very similar to today's armadilla and sloths in the same areas. He believed that these species evolved from these ancestors. Also, the most recent fossils most resemble current species.
Describe how Darwin’s finches are grouped together. What are the groups?
1) Pinsons de terre
2) Pinsons végétarien
3) Pinsons des arbres
4) Pinsons chanteurs
Why do we study evolving fossils
They appear in chronological order, so we can compare past organisms with more recent ones and observe changes in traits and the appearance of new adaptations over time.
Define artificial selection
Humans choose the particular traits of the organism they want . Humans cross organisms with these traits together to bring out its desired characteristics in offspring
Microevolution:
Populations of the same species, Observed for a shorter duration
Analysis: natural selection , variations in allele frequencies, changes, etc.
Macroevolution
Large populations of many common species.
• Observed over a long period of time Analysis: speciation takes place whic creates different species
natural selection:
-The most common characteristics are determined by the environment.
-Mutations that cause
different versions of a trait are random.
-Does not follow a predetermined plan Purpose: to increase survival in the organism. This is the reason why certain characteristics are chosen and inherited.
-Small differences that accumulate over a long period of time.
Artificial selection
-Characteristics transmitted are chosen by humans.
• The characteristics are not necessarily chosen to increase the chances of survival of the organism; rather for the wellbeing of humans or other reasons
• . Big differences present after a short period of time.