Exam 5 chapter 25 Flashcards
What is evolution
A heritable change in one or more characteristics of a population from one generation to the next
What was the idea of special creation
Species are independent (unrelated) – each species created independently
Life on Earth is young (approximately 6000 years old)
Species are immutable (no change; they are staying the same throughout time)
Describe Aristotle and the great chain of being
Species were organized into a fixed sequence based on increasing size and complexity
Humans were at the top of the chain
So, some species are higher, i.e. more complex or better than others
Who was the first to propose a formal theory of evolution? What was his theory
Jean-Baptiste de Lamarck
Simple organisms originate at the base of the great chain of being by spontaneous generation
Organisms evolve by moving up the chain over time
Lamarckian evolution is thus progressive – always producing better species
Describe what is meant by inheritance of acquired characteristics
Individuals’ phenotype changes in response to environmental challenges. Then these changes are passed onto their offspring.
Ex: muscles and giraffes
What is a population
A population consists of individuals of the SAME species living in the SAME area at the SAME time.
Darwin described evolution as
descent with modicfication
recent analyses of the fossil record suggest that 99+% of species that have ever lived are now extinct
true
Which of the following scientists developed a theory of evolution that was very similar to Charles Darwin’s
Alfred Wallace
Which of the following is an example of a vestigial trait
Eye sockets in eyeless cave fish
List 2 examples of organisms changing through time (AKA evolving
Bacteria evolving resistance to drugs
Insects have evolved resistance to pesticides
Define homology
Having similar characteristics with different organisms due to a common ancestor.
Ex: human and bat forelimbs
Convergent evolution
organisms not closely related evolve similar characteristics due to similar environmental conditions
genetic homology
A similarity in the DNA nucleotide sequences, RNA nucleotide sequences, or amino acid sequences
Developmental homology
Similarities seen in embryos of different species.
Ex: tails and gill pouches are found in the embryos of chickens, humans and cats
What is speciation
Process that results in one species splitting into two or more descendant species
Describe the difference between natural vs. artificial selection
Essentially the same process except in artificial selection, man is selecting for certain traits in plants and animals and breeds to enhance that trait; usually much quicker than natural selection. Natural selection is when organisms better adapted to their environment (more fit) tend to survive and produce more offspring
Fitness
ability of an individual to produce surviving, fertile offspring relative to that ability in other individuals in the population
Adaption
heritable trait that increases an individual’s fitness in a particular environment relative to individuals lacking that trait; adaptations increase fitness
Evolution is a change in the ___frequencies of a population over tim
allele
Which of the following is not an example of evolution through natural selection
Humans visiting high elevation regions develop a higher density of red blood cells
Do organisms sacrifice themselves for the good of the species
NO. Individuals with alleles that cause self-sacrificing behavior die and do not produce offspring, so these alleles are eliminated from the population
Does evolution act on individuals
no. selection acts on individuals and evolution acts on populations
Is acclimatization adaptation
NO. Acclimatization occurs when an individual’s phenotype changes in response to changes in the environment. The individual’s genotype remains fixed. Changes not passed on the offspring because no alleles have changed.
Are certain species higher than others
No. all evolved from a common ancestor
Which of the following is NOT an example of a fitness trade off
Plants with yellow flowers can produce a great number of seeds
