Adaption, Variation, Natural Selection Flashcards
What is an adaptation?
A structure, behaviour, or physiological process that helps an organism survive and reproduce in a particular environment.
Examples include hibernation and camouflage.
What are the three types of adaptations?
- Physical
- Physiological
- Behavioural
Each type contributes to the survival of an organism in its environment.
Identify the type of adaptation: The thick body plating of an armadillo.
Physical
Physical adaptations involve structural features of an organism.
Identify the type of adaptation: Lizards voluntarily detach their tail when threatened.
Behavioural
Behavioural adaptations involve actions taken by an organism.
Identify the type of adaptation: Reduced heart rate and breathing of a ground squirrel in hibernation.
Physiological
Physiological adaptations involve internal body processes.
Identify the type of adaptation: The needles of a blue spruce tree.
Physical
This adaptation helps the tree conserve water.
What do climbing feet help birds like woodpeckers do?
Climb trees
These feet have sharp nails for digging into wood.
What do swimming feet help birds like ducks do?
Paddle through water efficiently
Wobbed feet are adapted for swimming.
What adaptation do birds like emus have for running quickly?
Three toes, all of which face forward
This foot structure aids in speed.
What type of feet do perching birds like blue jays have?
Feet with four toes, one of which is in the back
This helps them balance on tree branches.
What type of feet do predatory birds like hawks have?
Clawlike feet called talons
Talons are used for grabbing prey.
What is variation in the context of adaptations?
A visible or invisible change in the characteristics of members within a population.
Variation can help individuals survive and is likely to be passed on.
Where does variation come from?
- Genetic
- Sexual reproduction
- Mutations
These factors contribute to the diversity of traits within a population.
What happens if a mutation is beneficial?
The organism will likely pass on the mutation (selective advantage).
Beneficial mutations increase chances of survival.
What happens if a mutation is detrimental?
The organism will likely die and not pass on the mutation (selective disadvantage).
Detrimental mutations decrease chances of survival.
What is an example of a beneficial mutation?
A mutation in a red blood cell gene causing sickle cell anemia that provides increased resistance to malaria.
Carriers of this gene do not exhibit the disease.
What is natural selection?
The process by which a population of organisms changes because individuals with certain traits can better survive and pass on these traits.
Natural selection drives evolution.
What is the process by which a population of organisms changes due to human selection?
Selection
Selection is when humans choose individuals with desirable traits to pass on to their offspring, seen in domesticated animals and crops.
Give examples of organisms that have undergone selection by humans.
- Dogs
- Cats
- Cattle
- Vegetables
These examples demonstrate how human influence has shaped various species through selective breeding.
What is genetic variation?
Variation in characteristics among individuals in each generation
Genetic variation is crucial for evolution as it provides the raw material for natural selection.
What does ‘survival of the fittest’ mean?
Individuals with favorable characteristics are more likely to survive and breed
This concept emphasizes the role of advantageous traits in the survival and reproduction of organisms.
Fill in the blank: In the natural environment, living organisms face problems such as _______.
competition, predation, and climatic conditions
These factors create challenges that influence survival and evolution.
What is a scientific theory?
An explanation that ties together various observations, enabling predictions about new situations
Scientific theories are foundational to scientific understanding and exploration.
Who are the two scientists credited with developing hypotheses related to natural selection?
- Charles Darwin
- Alfred Russel Wallace
Their work laid the groundwork for modern evolutionary biology.
What did Lamarck believe regarding the origin of new species?
New species arise spontaneously from non-living matter
This idea contrasts with Darwinian evolution, which emphasizes gradual change through natural selection.
What was one of Lamarck’s key ideas about organisms?
Organisms have a ‘desire’ to change for the better
This notion implies that organisms can consciously adapt to their environments.
Fill in the blank: According to Lamarck, the use and/or disuse of structures is _______.
passed on to offspring
This concept is known as Lamarckism.
Which of the following is an example of Lamarckism? 1) A male and a female pit-bull have had their tails removed, therefore their puppies will have no tails. 2) Two people with blue eyes will have blue-eyed children. 3) A man lifts weights 3 hours per day so that his future children will have big muscles like him. 4) A black cat breeds with a white cat, and some of the kittens are white with black spots.
3) A man lifts weights 3 hours per day so that his future children will have big muscles like him.
This example reflects the idea of acquired characteristics being inherited.
What did Charles Darwin do from 1831 to 1836?
Traveled the world aboard the HMS Beagle collecting data, specimens, and observations
His voyage was instrumental in shaping his theories on evolution and natural selection.
What is paleontology?
The study of fossils
Paleontology provides essential evidence for the theory of evolution.
What does biogeography study?
The distribution of species
Biogeography helps understand evolutionary relationships based on geographical locations.
What are transitional fossils?
Fossils that show intermediary links between groups of organisms
Transitional fossils help fill in the gaps in the fossil record.
What significant fossil evidence is found in the Burgess Shale?
Fossils of extinct species that lived over 500 million years ago
Some fossils are clearly ancestors of extant species.
What does embryology study?
The study of fetal development
Embryological evidence supports evolutionary theory by showing similarities in early development.
What type of evidence does molecular biology provide for evolution?
Evidence at the molecular level, such as DNA and protein similarities
Molecular biology can reveal evolutionary relationships between species.
How does the fossil record provide evidence for evolution?
Fossils found in upper rock layers resemble organisms alive today and are in order
Not all organisms appear at the same time, supporting evolutionary relationships.
What is the significance of geographic proximity in biogeography?
Geographically close environments are more likely to be populated by related species
This phenomenon explains why island animals resemble those on nearby continents.
What theory explains the distribution of species due to geological changes?
Theory of plate tectonics
This theory highlights how continental drift has affected species distribution.
What was Pangaea?
A supercontinent that existed 225-150 million years ago
The break-up of Pangaea contributed to the current distribution of species.
Fill in the blank: The fossil record is important because it shows that _______ appear at different times.
not all organisms
This provides further proof of evolutionary relationships.
What is the age of the oldest rocks dated on Earth?
4.6 billion years ago
This dating helps establish a timeline for the evolution of life.
