Zoo 1 Flashcards

individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than other individuals

--> leads to the accumulation of favorable traits in the pop. over generations

Interactions between the environment and organismal variation such that individuals with certain inheritable characteristics survive and reproduce at a higher rate than other individuals

One origin of life, or multiple origins.

Similarity due to common origin (Darwin's belief)

History of the development of an organism through its entire life. (from birth --> child --> adult)

Repeating the evolutionary stages of its ancestors during its own embryonic development. (Ontogeny recapitulates phylogeny)

Evolutionary change in timing of development

- shortening or lengthening of ontogeny results in a mosaic of different kinds of developmental evolutionary change in a single lineage

Occurs when populations occupy separate geographical areas. (Physical Barrier, become 2 species)

Type of Reproductive Barrier

Process of a new species evolving from a single ancestral species while living in the same environment but faced with different components.

Geographically intermediate between allopatric and sympatric speciation. (Same spot just in different locations, have a limited border)

Evolution occurs by the accumulation of small changes over time.

May explain the discontinuous evolutionary changes observed through geological time.

- Gradual change then sudden change over thousands of years

Evolutionary cooption of a biological character for a role unrelated to the character's evolutionary origins

- structures are used for something else, than initially intended for

Combines knowledge about genes, chromosomes and inheritance with Darwin's theory

Studies evolution as change in gene frequencies in populations. (looking at genes now --> overtime)

Evolutionary changes in frequencies of different allelic forms of genes.

Evolution on a grand scale with origins of new structures and designs, trends, mass extinctions, etc.

Changes in allele frequencies (measurable --> can see overtime)

Change in DNA sequence (due to error in DNA replication and external sources like chemicals, radiation, or U.V. sunlight)

Transfer of alleles between populations (genes moving together, can see the diff in genes and alleles from parents)

Occurs when chance events alter allele frequencies (typically happens with a small populations) --> based on luck not fitness

A loss of genetic variation that happens when a new population is started by a small group of individuals from a larger parent population. (ex. amish)

A sharp reduction in population size and genetic diversity caused by a random event. (survival is based on luck not traits)

Selection within the same sex.

(mate choice) Individuals of one sex are choosy in selecting their mate from the other sex.

An aggregation of undifferentiated cells. Cells all have the same function.

Aggregation of cells that are functionally differentiated. Division of labor, each cell has a different function: reproduction, digestion, respiratory, etc.

Bilateral

An arrangement of body parts or shapes around a central axis. Object can be divided into identical halves.

Having 2 sides or halves that do not match or are not the same size, shape, and arrangement.

Sensory apparatus, concentration of sensory organs at the front or anterior end (to form a head).

Ex. jelly fish have organs everywhere --> no sense of direction, humans have organs facing front (associated with bilateral animals--> move in one direction)

Initial cell division of zygote

Space for organs, fluids, etc

Increases SA and complexity

Cells developmental fate determined by cytoplasmic components (proteins, mRNA's) (cell fate)

Process in early animal development that independently differentiates each part of embryo. (cell fate)

Cell is induced to a particular fate by neighboring cells; cell fate changes if moved in embryo. (cell fate)

Molecules that influence cell fate diffuse within the the cytoplasm of a single large, multi-nucleated cell. Seen in Arthropods (cell fate)

A signaling molecule that controls tissue development and pattern formation by spreading through tissue to establish gradients in the embryo.

Serial repetition of similar body regions along the anteroposterior axis of the body. ex. worms, fish

2 colors match under one specific light source but look different when light changes. (only 3 phyla have: annelids, arthropods, chordata)

Plan and placement of body parts during embryonic development. Master genes that specify a location within the body.

Cleavage planes are symmetrical to the polar axis, producing layers of cells on top of each other, regulative.

Regulative Development - no fixed fates initially, communicate with neighboring cells and environment

ex: humans, fish, sea urchins

Cleaves oblique (off-center of axis) to axis and typically produces a quartet of cells that lie in furrows between the cells; mosaic.

Mosaic Development - predetermined cell fate

ex: snails, worms

Hallow ball of cells that forms during early animal embryonic development.

Ball of cells surrounding a fluid-filled cavity

Hallow ball of cells (blastula) reorganizes into a structure with multiple tissue layers

The outer derm layer surrounding blastocoel

The inner layer of blastocoel, surrounding inner cavity.

The inner body cavity of a blastocoel

2 layers, 3 layers of tissue

A fluid-filled body cavity that is completely lined with tissue derived from the mesoderm and surrounds the digestive tract and internal organs. Allows for protection (shock absorber), movement (shift shape), support (hydrostatic), circulation (transporting gases, nutrients, waste products)

A fluid filled cavity that lies between the body wall and the digestive tract. Mesoderm lines the outer edge of the blastocoel.

No body cavity, the space between the digestive tract and outer body cells is completely filled with tissue. Mesoderm completely fills the blastocoel.

A fluid filled cavity New cavity completely lined with a middle tissue layer called mesoderm. MOST SA - has largest body cavity.

An embryonic development process that interally splits to form the fluid-filled body cavity. Mesodermal cells migrate to blastocoel to form the coelom.

Coelom pinch off from pouches of the gut that push outward into the blastocoel.

Phyla that consist of bilateral animals with three germ layers

Form of embryonic development where "mouth first"=blastopore becomes mouth, spiral mosaic cleavage, triploblastic, coelomates form via schizocoely

Molt their cuticles - shedding animals

Bilateral symmetry, spiral cleavage, triploblastic animals with protostomes(first opening in embryo develops into the mouth)

Most have trochophore larval stage - free-swimming stage, moving via cillia

"Mouth second" = blastopore become the anus, radial regulative cleavage, all are coelomates, vertebrate members form their coelom via schizocoely, Enterocoelous

Formal system for naming and classifying species

Broader science of comparative biology

Kingdom, Phylum, Class, Order, Family, Genus, and Species (King Phillip Came Over For Good Soup)

Names of groups at each rank in the biological classification system to categorize organisms

Linnaeus's system for naming species

The evolutionary history of an organism or taxa of organisms

Studying organismal features, including: morphological, biochemical, chromosomal, and molecular features.

Character similarity that misrepresents common descent (looks similar but misrepresents descent)

ex: bird and bat wings

The character state present in the common ancestor.

Variant forms of the character traits that arose later within the group

The ancestral/descendant relationships among the variant forms of a character.

Group that is phylogenetically close but not within the group being studied.

Prefer the simplest hypothesis capable of explaining the observations. Simplest explanation is the correct one.

Species that share derived character states form subsets within the study group.

Derived character shared by members of a clade. Used as evidence of homology. Finding a clade then we know the organisms are all related to each other.

Pattern of derived states of characters within study group forms clades within clades.

Smaller groups fit completely inside larger groups.

Includes the most recent common ancestor and all descendants of that ancestor.

Includes the most recent common ancestor of all members of a group and some but not all descendants of that ancestor.

Does not include the most recent common ancestor of all members of a group; has at least 2 separate evolutionary origins.

Accounts both for common descent and adaptive evolutionary change. Taxa may be monophyletic or paraphyletic, REJECTS polyphyletic grouping.

- A distinct adaptive zone may merit its own taxon (ex. Hominidae)

Emphasizes common descent and cladograms. Rejects paraphyletic and polyphyletic groups. (only likes evolutionary history, common ancestors evolving)