IB Biology: Evolution

What is an adaptation?

A trait that has evolved due to natural selection that increases the chance for survival and/or reproduction.

What is artificial selection?

Selective breeding. Choosing the best crop and using that, or choosing the best/most fit dogs and breeding them.

What are the five classes of vertebrates?

Bony ray-finned fish, amphibians, reptiles, birds, and mammals.

Describe the characteristics of the bony ray-finned fish.

Bony-plate scales in the skin, one gill slit covered by an operculum, no limbs, fins supported by rays, external fertilization, remain in water, swim bladder contains gas, do not maintain constant body temp.

What are cladograms?

Tree diagrams that show the most probable sequence of divergence in clades.

What is a theory?

A comprehensive explanation of some aspect of nature (vs a hypothesis, which is just a prediction as to the result of an experiment).

What is a clade?

A group of organisms that have evolved from a common ancestor, and include all living and extinct organisms.

What is the smallest group of organisms that can evolve?

A population, which is a group of individuals of the same species in the same area at the same time.

Define acquired vs heritable traits.

Acquired traits are ones that occur during a species' lifetime, ex. a broken bone or an ear piercing; heritable traits are ones that pass from parent to offspring.

What are the three domains and what are their characteristics?

Bacteria, unicellular and prokaryotic, cell wall w/ peptidoglycan; Archaea, unicellular and prokaryotic, cell wall w/o peptidoglycan; Eukarya, eukaryotic

What are the six kingdoms and what are their characteristics?

Bacteria, unicellular organisms; Archaea, unicellular organisms in extreme environments; Protista, unicellular complex organisms; Fungi, uni/multicellular and absorb food; Plantae, multicellular and make their own food; Animalia, multicellular and consume their food.

What is sympatric speciation?

Behavior, temporal, or anatomical reproductive isolation.

What are the four plant phyla?

Bryophyta (mosses, liverworts, hornworts), Filicinophyta (ferns), Coniferophyta (conifers), Angiospermophyta (flowering plants).

In which era did the age of mammals happen?

Cenozoic

What is the hierarchy of classification and what is the mnemonic device?

Dear King Philip Came Over For Great Soup! (Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species)

Give the chronological order of the following events: appearance of human ancestors, life first appears, earth is formed, multicellular animals appear.

Earth is formed, life first appears, multicellular animals appear, appearance of human ancestors.

What are the four principles of natural selection?

First, that organisms produce more offspring than can be supported by the environment. Second, that offspring are not identical and there is variation within a population. Third, individuals compete for resources. Fourth, the individuals that are more successful at obtaining food, territory, and mates will have a better chance of survival and therefore more offspring.

What does survival of the fittest mean?

Fittest = the ones with the most reproductive success, not necessarily the biggest or the strongest. The most fit have the most offspring and pass on their genes.

How do the fossils scientists have recovered support the theory of evolution?

Fossils are chronological; however deep they are in the Earth is a rough estimate of how long they've been there. Fossils proved how old the Earth was and how things had changed over time.

What were some ideas from Darwin's time that influenced his work?

French naturalist Buffon in the mid-1700s studied fossils and said the Earth must be older than previously assumed; Lamarck in the early 1800s proposed that life changes over time.

What causes variation in a population?

Genetic mutations, meiosis (the combination of new alleles), and sexual reproduction.

How do you identify and write a Latin species name according to the Linnean system?

Genus species, ex. Homo (genus) sapiens (species), Canis lupus, canis latrans, etc. Always capitalize the first and don't capitalize the second. Italicize the name in a report or paper.

What are the four types of reproductive isolation?

Geographical (physically), temporal (mating times are misaligned), behavior (mating behavior is dissimilar), or anatomical (sexual organs are incompatible).

What are the two theories of evolutionary change?

Gradualism, a slow even change; or punctuated, long periods of no change with bursts of rapid change.

What was a flaw in Lamarck's theory of evolution?

He saw "acquired traits" as the driving force behind evolution rather than heritable traits.

Describe the characteristics of reptiles.

Impermeable skin covered with keratin scales, complex lungs, four limbs, internal fertilization, soft shelled eggs, teeth of all one type with no living parts, do not maintain constant body temp.

What four things cause changes in gene pools?

Natural selection, reproductive isolation, random events (genetic drift, like a natural disaster), and mutations introducing new alleles.

Can an individual evolve?

No.

How does geographic distribution support the theory of evolution?

Organisms on separate parts of the world shared traits because of biogeography and convergent evolution.

What is descent with modification?

Over many generations, adaptations could cause species to evolve into new species; all species are descended from a common ancestor.

In which era did the first amphibian appear?

Paleozoic

In which era did the first shelled animals appear?

Paleozoic

In which era were the first land plants and animals?

Paleozoic

Which era was dominated by reptiles?

Paleozoic

What is plant speciation?

Plants can evolve through polyploidy (contributing extra chromosomes, typically an entire set). Often produces a species that is reproductively isolated and distinct from "parent" species.

What are the six animal phyla?

Porifera (sponges), Cnidaria (hydras, jellyfish, corals, sea anemones), Platyhelminthes (flatworms, flukes, tapeworms), Mollusca (bivalves, gastropods, snails, squid, octopus, chitons), Annelida (marine bristleworms, oligochaetes, leeches), Arthropoda (insects, arachnids, crustaceans, myriapods).

In which era did the first living organism appear?

Precambrian

In which era did the first multicellular organism appear?

Precambrian

In which era did the photosynthesis and oxygen increase?

Precambrian

What is the order of the four eras?

Precambrian, Paleozoic, Mesozoic, Cenozoic

What were key observations from Darwin's voyages that led to his theory?

Saw that on different Galapagos Islands, there were finches that were all separate species but must have shared a common ancestor despite being isolated and endemic species.

What are homologous structures and how do they support the theory of evolution?

Similar structures in species that share a common ancestor yet are now separate. They support evolution because similar structures give the idea that two separate species may have once been one and the same.

What are analogous structures?

Similarities in structures that have become similar because the organisms have adapted to similar environments.

Describe the characteristics of mammals.

Skin has follicles with hair made of keratin, lungs with alveoli, diaphragm, four legs/two wings & two arms, internal fertilization, live young, milk from mammary glands, teeth of different types with living core, maintain constant body temp.

Describe the characteristics of birds.

Skin with feathers made of keratin, lungs with para-bronchial tubes, air sacs, two legs and two wings, internal fertilization, hard shelled eggs, beak but no teeth, maintain constant body temp.

Describe the characteristics of amphibians.

Soft moist skin, simple lungs, four limbs when adult, external fertilization, larval stage in water and adult stage on land, eggs coated in protective jelly, do not maintain constant body temp.

What are the three patterns of natural selection?

Stabilizing, disruptive, and directional.

What are the two main points of Darwin's theory?

That natural selection occurs and that there is descent with modification.

What is molecular evolution?

The DNA of species can be tested to check for similarities with other species. The evolution of DNA leads to new species.

What is evolution?

The change in the heritable traits of biological populations over successive generations.

What is a gene pool?

The total number of genes in a particular population.

What are the goals of modern taxonomy?

To identify, name, and classify new species.

What are vestigial structures and how do they support the theory of evolution?

Vestigial structures are remnants of structures that no longer serve a purpose, ex. the appendix and the muscles that give us goosebumps. They support evolution because they show that we used to have a function for them but evolved to no longer require them.

What is genetic equilibrium?

When all members of a population have an equal chance of contributing to the future gene pool (doesn't actually happen in nature).

What is directional natural selection?

When natural selection moves toward one extreme that is better adapted to the environment.

What is disruptive natural selection?

When natural selection moves toward the extremes and away from the average.

What is stabilizing natural selection?

When natural selection removes the extremes from the population and goes toward middle ground.

What is divergent evolution?

When one species evolves in two different directions due to experiencing separate environments.

What is reproductive isolation?

When populations become isolated from one another and can no longer reproduce together.

What is convergent evolution?

When species who evolved separately develop similar traits because they are adapting to similar environments.

What is allopatric speciation?

When two populations are separated by a physical barrier and evolve into separate species that can no longer reproduce with each other.

What is speciation?

When two populations separate and evolve into separate species.

How are humans classified?

[D]-Eukarya, [K]-Animalia, [P]-Chordata (hollow nerve chord), [C]-Mammalia (middle ear bone, hair, milk production), [O]-Primates (opposable thumbs, fingernails, expanded forebrain, binocular vision), [F]-Hominidae (no tails, ex. chimpanzee), [G]-Homo (tool use, language, culture), [S]-Homo sapiens