Honors Biology Final Study Guide
nondisjunction- failure of one or more homologous pairs of chromosomes to separate during meiosis (could also occur if
sister chromatids fail to separate)
monosomy- genetic condition in which a cell or zygote receives only one chromosome of a particular homologous pair (ex.
in humans if you only received 45 chromosomes which could also be Turner’s syndrome for a girl)
trisomy- genetic condition in which a cell or zygote receives an extra chromosome of a particular homologous pair (ex. in
humans if you received 47 chromosomes, that would be trisomy 21 also known as Down Syndrome, another example is
Klinefelter’s syndrome in boys)
polyploidy- genetic condition in which a cell or zygote has 3 or more complete sets of chromosomes, result of
nondisjunction occurring in all the chromosome pairs, this would most likely result in death (ex. in humans if you received 69
chromosomes)
autosome- any chromosome other than a sex chromosome (in humans 22 pairs of autosomes, 44 autosomes)
karyotype- image of a cell’s chromosomes arranged by size and in homologous pairs (sex chromosomes placed last),
made by blocking cells during mitosis and staining them, dye stains regions of chromosomes that are rich in base pairs
adenine and thymine producing a dark band
amniocentesis- technique where a needle is inserted into the amniotic sac of a pregnant woman (amniotic fluid is extracted
and contains fetal cells that can be cultured in the lab), usually done in woman’s 15-16th week of pregnancy, results come
back in 10-14 days, determination of gender can be made in 1-2 days (process is very accurate, little risk)
chorionic villi sampling- technique where chorion tissue is extracted from the mother and a biopsy is done on it, this is
done in the 10th - 12th week of pregnancy, results come back in 2 weeks or less, reliability is less than those of
amniocentesis, risk of causing a miscarriage due to this procedure is 1-3% or 2-6 times greater than amniocentesis
pedigree- diagram that shows the inheritance of a specific trait in a family, may be used to determine the probability of a
disease being inherited by children, rules for completing a pedigree:
a. place squares and circles for males and females in a family
b. shade in anyone who has the trait (write in homozygous recessive alleles)
c. anyone who doesn’t have the trait most have at least one dominant allele
d. children must have a recessive allele if one of their parents had the trait
e. shade in half of the symbols that are heterozygous because they are carriers
f. it may not be possible in all cases to determine if some are homozygous dominant or heterozygous from the
information given
sex-linked recessive- also known as X linked, alleles found on sex chromosomes, traits are recessive, trait is far more
common in males, males cannot be carriers, daughters of males who have trait are either carriers or will have the trait, if
mother has trait so will any sons she has
sex-linked dominant- also X linked, alleles found on sex chromosomes, traits are dominant, no carriers, daughters of a
male who has the trait will also have the trait, no inheritance between father and son (sons only inherit from mothers)
autosomal recessive trait- alleles found on autosomes, traits are recessive, males and females are equally likely to have
trait, traits often skip a generation, children can have trait if both parents are carriers
autosomal dominant trait- alleles found on autosomes, traits dominant, no carriers, males and females are equally likely to
have trait, traits do not skip a generation
Down Syndrome- chromosomal abnormality, also known as trisomy 21, 47th pair of chromosomes, chromosome 21,
symptoms are various levels of mental retardation, lower life expectancy (although some can live past 50 years), short body,
enlarged tongue, stubby fingers, the head is usually small and round, heart defects are common, they are fertile, likelihood
increases as the mother’s age increases
Klinefelter Syndrome- chromosomal abnormality, 47th pair of chromosomes, sex chromosomes XXY, 1 in 1,000 births,
occurs in males, usually sterile because they cannot produce sperm, enlarged breast tissue, often lack secondary sexual
characteristics such as facial hair, but they do have some feminine body contours, slightly lower IQ’s, treatment may involve
additional male sex hormones
Turner Syndrome- chromosomal abnormality, 45th pair of chromosomes, XO, 1 in 2,500 births, occurs in females, usually
sterile because sex organs do not fully develop, short body and hands, stocky build, sometimes extra folds of skin on the
neck, arms turn out slightly at the elbows, secondary sexual characteristics may not fully develop
PKU- autosomal disorder, recessive allele on chromosome 12, 1 in 10,000 births, individuals lack enzyme that is needed for
the metabolism of amino acid phenylalanine, digestion of phenylalanine leads to production of toxins that damage nerve
cells in children, causes developmental disabilities, mental retardation, and eventual death, treatments include a special diet
that is low in phenylalanines until the brain is fully developed (avoid milk, meats, and high-protein foods)
Cystic Fibrosis- autosomal disorder, recessive allele on chromosome 7, 1 in 2,500 births, defect leads to build up of
chloride ions inside the cell that draws water from fluids outside the cell, surrounding mucus becomes thick and heavy and
clogs lungs, respiratory passages, digestive tract (impairs gas exchange and secretion of digestive juices), treatments
include mechanical vibrations to loosen mucus, antibiotics to fight infection, management of diet, and experimental gene
therapy
Huntington’s Disease- autosomal disorder, dominant allele on chromosome 4, 1 in 10,000 births, symptoms do not appear
until late 30’s or 40’s (allele may have already been passed on to next generation), individuals usually die within 10-20 years
of initial symptoms, symptoms include deterioration of the brain’s basal ganglia, loss of muscle control, twitching movements
of limbs and body, loss of memory, dementia, no cure (interesting because most fatal diseases are on recessive alleles and
most dominant diseases kill before the children are born except Huntington’s)
gel electrophoresis- a process by which molecules are sorted by size as they are pulled by an electric current through gel
DNA fingerprinting- technique that compares the pattern of DNA bands from a suspect, produced during gel
electrophoresis, with the pattern of bands from the DNA evidence, DNA fingerprinting helps identify blood donors, genetic
disease, dead bodies, and determine paternity tests
bands- each is composed of thousands of DNA fragments, bands that have traveled equal distances consist of fragments
that are the same length, but not necessarily the same sequence
restriction enzymes (uses and naming)- restriction enzymes are proteins that cut DNA sequence, they are named first by
the scientific name of the bacterium, then the strain, lastly the order in which the bacterium was found, ex. EcoR2
restriction sites- (recognition sites), these sites at the 4 to 8 base pairs is where the DNA is cut by restriction enzymes
restriction maps- pattern where DNA is cut and then stuck back together
Southern Blotting- (hybridization), procedure in which DNA is transferred from gel to a membrane filter and hybridization
with a DNA probe, x-ray film can be placed over the membrane to produce an autorad that mirrors locations of targeted
DNA bands on the gel
sticky ends- the sequence of DNA is cut in a zig zag form so the DNA can stick together with another hanging sequence
(there are exposed nucleotide bases that can stick together)
PCR processes- (amplification), technique that uses DNA polymerase to make copies of a specific section of DNA (DNA
can be copied millions of times in a matter of hours, simulates DNA replication)
sex-linked traits- traits whose alleles are located on sex chromosomes, in humans many more alleles are found on the X
chromosome than on Y chromosome (these are also called X linked), examples are hemophilia, red-green colorblindness,
Duchene muscular dystrophy, if a genetic disorder involves recessive alleles:
a. heterozygous females do not express the trait, but are carries
b. females will only express the trait if they are homozygous recessive
c. males only receive one X chromosome (one allele); they will express the trait if they have a recessive allele
d. males are more likely to be hemophiliacs or colorblind
e. males inherit these alleles and traits from their mothers
genotypes should include the sex chromosomes and the alleles are used as superscripts ex. XHXh, XhY
ex. Carol is heterozygous for hemophilia. Her husband does not carry the allele for hemophilia. What is the probability they
will have a daughter with hemophilia? A son with hemophilia?
XHXh * XHY
H = normal, h = hemophiliac
XH
Xh
XH
XHXH
XHXh
Y
XHY
Xh Y
genotype: XHXH, XHXh, XHY, XhY
phenotype: female- 100% normal, male- 50% normal, 50% hemophiliac
sex-limited traits- alleles are located on autosomes, expressed in the presence of the sex hormones of one sex, but not
the other sex (trait is limited to one sex), ex. milk production in female mammals, color of plumage in birds
sex-influenced traits- alleles are located on autosomes, expressed in both sexes, but expressed differently, involves
response to sex hormones, ex. baldness
DNA fingerprinting- technique that compares the pattern of DNA bands from a suspect, produced during gel
electrophoresis, with the pattern of bands from the DNA evidence, DNA fingerprinting helps identify blood donors, genetic
disease, dead bodies, and determine paternity tests
plasmid- small, circular piece of DNA found in bacteria (separate from the chromosome)
recombinant DNA- DNA that contains fragments derived from two or more different sources
selective breeding: also known as artificial selection, technique that only allows those organisms with desirable traits to
mate and produce the next generation
cloning- technique that produces an individual that is genetically identical to another organism (haploid nucleus extracted
from the egg of a donor, diploid nucleus taken out of a cell from a donor, this nucleus is put into the egg and planted back in
the egg donor’s body, since the cell is diploid it believes it is already fertilized, with a tiny electric shock the cell begins
growing into an organism, offspring is an exact clone as the cell donor)
transformation- process of inserting recombinant DNA into a living cell (involves a vector)
gene therapy- practice of inserting functional genes to do work for nonfunctional genes, involves either replacing,
manipulating, or supplementing nonfunctional genes with healthy genes
transgenic organisms- organism that has been genetically engineered to contain DNA from a different species
short tandem repeats- (short STR or variable VNTR), consists of simple, repetitive sequences of DNA found mainly in the
intergenic regions of a chromosome, tend to differ from person to person and are often used to produce a “DNA fingerprint”
Barr body- an inactive X chromosome that condenses into a compact object in the cells of female mammals during
embryonic development (which of the X chromosomes becomes the Barr body occurs randomly and independently in each
cell), chromosome looks like dense circle, ex. cats (genes determine color of the fur, orange, black, or white), sometimes
females have the genes for both orange and black or vice verse and one is deactivated and becomes a Barr body, Calico
cat = 99% of time a female because it has orange, white, and black (because of the two X chromosomes), Tortes shell cat =
black and orange fur (most of the time female), remember that every cell has to go through this process, that is how you get
some cats with black and orange or some with white and black and vice versa
applications and objectives of the Human Genome Project- objectives: map the entire base sequence of every
chromosome in the human cell, identify all the genes in the base sequence, determine what proteins the genes code fordetermine the exact role of each gene, identify the gene location and base sequence for genetic diseases, applications:
diagnosis of specific genetic diseases (ex. PKU) and screen for a position to other diseases (other types of cancer), help
produce drugs and proteins to treat specific genetic diseases, increases the ability to research the effects of mutations of
genes, increases our understanding of evolution and taxonomic relationships, gives insight into the structure, function, and
organization of DNA in chromosomes, medical benefits: improved diagnosis of disease and predisposition to disease by
genetic testing, better identification of disease carriers, through genetic testing, better drugs can be designed using
knowledge of protein structure rather than by trial and error, greater possibility of successfully using gene therapy to correct
genetic disorders, non-medical benefits: greater knowledge of family relationships through genetic testing, advances
forensic science through the analysis of DNA at crime scenes, improved knowledge of the evolutionary relationships
between humans and other organisms, which will help to develop better, more accurate classification systems, ethical
issues: it is unclear whether 3rd parties have rights to genetic test results, if treatment is unavailable for a disease then
genetic knowledge about it may have no use- genetic tests are costly, and there is no easy answer as to who should pay for
them, genetic information is hereditary so knowledge of an individual’s own genome as implications for members of their
family
advantages and disadvantages of transgenic plantsadvantages:
disadvantages:
may keep away unwanted insects such as pests
may kill other insects that aren’t harmful such as Monarchs
more of the plant may be able to grow
superbugs may evolve and resist the plants (and superweeds)
naturally produced by the plant
cloning plants reduces the genetic diversity
genetically modified food (issues)advantages:
disadvantages:
foods may becomes more nutritious
presence of pesticides may be harmful
extends shelf life
genetically modified foods could trigger allergies
crops can possibly become edible vaccines
religious morals
golden rice- genetically engineered rice that is inserted with beta-carotene (that gives the rice its orange glow); the betacarotene is converted to vitamin A when digested, this rice is more nutritious
Bt corn- Bt corn is a bacterium that kills insects contaminating crops, this bacterium has raised concern though because it
is has killed Monarch butterflies in the past, an endangered species, and now researchers are trying to alter the Bt corn so it
does not kill Monarchs
fitness- an organism’s ability to survive and reproduce in a particular environment
gradualism- states that small evolutionary changes occur slowly and steadily over long periods of time, this process yields
many transitional forms
punctuated equilibrium- (Gould and Eldredge, 1972) states that a population tends to remain relatively stable for long
periods of time interrupted by periods of relatively rapid evolutionary change  explains gaps in the fossil record
natural selection- process in which organisms with favorable variations are more likely to survive and reproduce, these
variations are passed to the next generation, ex. antibiotic resistance in bacteria
1. stabilizing selection- favors intermediate phenotype, the most common, b/c they are more fit than extreme phenotypes,
the least common, evolution is minor or absent, ex: weight of human infant
2. directional selection- favors extreme phenotype b/c they are more fit than other phenotypes, evolution moves in a specific
direction, ex: size of human brains (larger and larger brains over time), size of horses (gaining size over time), color of
Peppered Moths (light color to dark color for survival on lichens of trees)
3. disruptive selection- favors extreme phenotypes that deviate in both directions, both extreme phenotypes have higher
fitness, evolves into two populations with distinct traits, ex: beak size in African finches (large and small beaks were
favorable, not medium sized. over time, small and large were more popular b/c medium sized beaks were less popular and
helpful
variation- differences that exist between members of the same species (these are the raw material of evolution). ex: size,
color, blood type
inbreeding- crossing of genetically similar organisms to maintain the presence of certain desirable traits  tends to
increase homozygous genotypes for both desirable and undesirable traits. ex: purebred dogs are more likely to have joint
deformities and blindness
outbreeding- (hybridization): crossing of genetically dissimilar organisms to bring together the best of both organisms 
tends to increase heterozygous genotypes and vigor (health). ex: mule of liger
adaptation- an inherited trait that helps an organism survive in its environment  a beneficial variation. ex: structural,
behavioral, physiological
population- group of organisms of the same species that live in the same area
analogous structures- refers to parts of two different species that are similar in function, but not in structure, ex: wings of a
bird and the wings of a butterfly, (not a result of a recent common ancestor but a result of the species having evolved in
similar environments  does not show a close evolutionary relationship)
Malthus- wrote an “Essay on the Principle of Populations”, stated that human babies were being born faster than people
were dying, human population could outgrow their resources such as living space and food supply, states that factors such
as war, famine, and disease help keep population in check, Darwin will apply these principles to all organisms- not all
organisms born will survive and those that survive will have to compete for limited resources
Lamarck- believed fossil record showed evolution has occurred and presents a theory to explain it
1. tendency toward perfection- organisms have an innate tendency to try to improve themselves
2. use and disuse- organisms could change the size and shape of their structures by either using them in new and
different ways or by not using them, ex. giraffes get longer necks, four-legged reptiles become snakes
3. inheritance of acquired characteristics- traits that are changed during an organism’s lifetime can be inherited by
their offspring (this theory is wrong because it only changes in DNA of gametes will be inherited by next generation)
Lyell- Principles of Geography, Lyell studied geologic deposits and determined that geologic forces (erosion, glaciers)
showed that earth was shaped by slow progressive changes, not catastrophic events such as floods; therefore the earth
must be millions of years old
Darwin- sailed on ship HMS Beagle as its naturalist for five years, collected numerous samples and fossils, in Galapagos
he studied many animals such as finches, diversity of these species greatly influenced his thinking on evolution, published a
book On the Origin of Species By Means of Natural Selection, his theory of evolution explains how species become extinct,
how species change over time, and how evolution takes place
Wallace- developed a theory of evolution nearly identical to Darwin’s, wrote a paper called “On the Tendency of Varieties to
Depart Indefinitely from the Original Type”, sent a copy to Darwin, asked for some advice, and told him he was going to
present his theory, this motivated Darwin to present his theory to the Linnaean Society
Cuvier- studied fossils and helped develop paleontology (particularly vertebrate), key role in proving extinctions did occur,
believed extinctions were a result of periodic catastrophes (revolutions), did not believe in evolution, believed species are
immutable (fixing and unchanging), explains after a catastrophe species immigrate from other regions to repopulate those
areas
Bonnett- naturalist, discovered parthenogenesis in aphids, observed that fossilized organisms did not resemble modern
organisms, believed in evolution and an evolutionary ladder, believed organisms perished in periodic, worldwide
catastrophes that wiped out all life, organisms were brought back after “stepping up” a rung in the evolutionary ladder, ex.
apes became humans, humans became angels
Morgan- fruit flies, XX and XY, predicted crossing over occurred, won Pulitzer prize, genes are linked because they are on
same chromosome and tend to be inherited together, crossover frequencies can be used to predict the distances between
genes on a chromosome and can map them
Bateson and Punnett- studied bees and heredity
Sutton- created the chromosome theory of heredity
evidence of evolution- all organisms were created relatively recently and have remained unchanged since that time,
species do not go extinct
evolution- process by which a species changes over time
fossils- preserved remains or traces of ancient organisms
homologous structures- structures found indifferent species that are similar in structure, but not necessarily similar in
function, evolved from a common ancestor
vestigial structures- structures that have no or a reduced function in organisms, ex. appendix and tailbone in humans,
vestigial hind limbs in some pythons, wings in flightless birds such as the rhea and emu, these structures evolved from an
ancestor that had a greater need fro them, difficult to explain their existence without evolution (not intelligent design)
comparative biochemistry- compares the DNA and proteins of different species to see how similar they are, evolved from
a common ancestor, ex: gorillas and humans are related in some way b/c similarities on the chromosome (traces of
telomeres and centromeres) that lead to it originally being two separate chromosomes like that of a gorilla
biogeography- studies the distribution of organisms in different parts of the world, explains why regions that are separated
by large physical barriers (oceans) but have similar environments, would contain different species rather than the same
species, ex. no large hooved-animals (deer) or native placental mammals are found in Australia even though it has suitable
habitat, Mediterranean Europe and California have virtually no plants in common despite similar habitats, often islands
(Hawaii & Galapagos) have many species which are found nowhere else (endemic), this occurred because the populations
evolved differently in one region than they did in another
radiometric dating- rocks or fossils may contain elements that are radioactive, the breakdown of these radioisotopes
occurs at a constant rate and can therefore be used as a geologic “time clock”, the parent isotope breaks down through a
series of steps to form a daughter product, scientists use the ratio of parent isotope to daughter product to determine how
many half-lives have passed and then calculate how old the sample is, the age is given in years, but they are not reliable
after eight half lives
half-life- length of time it takes for exactly one-half of the parent atoms to decay to daughter atoms, ex. carbon-14 dating,
potassium-40 dating, rubidium-87 dating, uranium-238 dating, and uranium-235 dating
nonvascular plants- bryophytes, gametophyte stage is dominant, lack vascular tissue, they do NOT have true roots,
stems, or leaves, reproduce using spores and NOT with seeds, require water for sexual reproduction (so the sperm can
swim to the egg), tend to live on land in moist habitats, ex. mosses, liverworts, hornworts
seedless vascular plants- sporophyte stage is dominant (true for all vascular plants), they have vascular tissue
(tracheophytes), they DO have roots, stems, and leaves, reproduce using spores NOT seeds, require water for sexual
reproduction (so the sperm can swim to the egg), ex. ferns, whisk ferns, horsetails, club mosses
gymnosperms- “naked seeds”, tracheophytes, bear their seeds directly on the surfaces of the cones, sporophyte stage is
dominant (true for all vascular plants), they are vascular plants, male cones contain pollen, female cones produce ovules
which will become seeds if they are fertilized, WIND pollinated (meaning they don’t rely on birds or insects to pollinate the
plants), ex.
1. conifers: have needle-like leaves, most are evergreens, all are cone bearing, pines, spruces, firs, cedars,
and redwoods
2. cycads: palm-like plants (not palm trees), found in tropical and subtropical regions including Florida
3. gingkoes: only one species remains, considered a living fossil, doesn’t appear to have evolved much
over time, diecious
4. gnetophytes: only three genera, one found in southwestern USA
rhizoid- root like structure that anchors nonvascular plants
capsule- small sac that contains spores in mosses (spore case of a moss plant), top part is the operculum
spore- haploid reproductive cells (can germinate without being fertilized)
sporangia- (plural of sporangium), spore case
antheridium- male reproductive structure that produces flagellated sperm (in non-vascular plants)
archegonium- female reproductive structure that produces a single egg (in non-vascular plants)
frond- leaf of a fern sporophyte
prothallus- gametophyte of a fern (heart-shaped)
sorus- (singular, plural would be sori), cluster of sporangia (spore cases) in ferns (often found on the underside of the frond)
gemmae- cuplike structures in liverworts that contain haploid cells capable of asexual reproduction
xylem- vscular tissue that transports water and minerals throughout parts of a plant
phloem- vascular tissue that transports dissolved sugars and starches
alternation of generations- process in which plants switch between haploid and diploid stages of their life
cycle
sporophyte (2N)
fertilization
meiosis
gametes (N)
spores (N)
germination
gametophyte (N)
2N = diploid, N = haploid
challenges of plants and colonizing land (evolution of plants)- aerial parts of plants prone to dessication  evolved
waxy, waterproof covering (cuticle), gametes and embryo exposed to environment  evolved multicellular protective
gametangia, air is a less supportive medium than water  evolved “internal skeleton” to support plant against the pull of
gravity, aerial parts of plants need source of water and minerals  evolved vascular system, terrestrial environment subject
to more dramatic and relatively rapid fluctuations in temperature, humidity, and wind  evolved changes in life cycles and
structures
benefits of terrestrial life (compared to the water)- greater availability of sunlight, increased levels of CO2, initially were
decreased levels of predation
four kinds of nucleotides- named after their nitrogen base, a. adenine (A), b. thymine (T), c. cytosine (C), d. guanine (G),
every cell has 6 billion nucleotides (3 billion pairs)
leading strand- DNA strand that replicates in the direction that follows the movement of the replication fork
lagging strand- DNA strand that replicates in the direction opposite the movement of the replication fork, DNA forms in
fragments (Okazaki fragments, 100-200 nucleotides long) that later are connected by DNA ligase (also known as DNA
polymerase)
antiparallel- sugar phosphate backbone of two DNA strands that run in opposite directions
histones- proteins that bind to DNA and helps fold DNA into chromatin, also creates nucleosomes, (DNA in humans would
be one meter long if not folded)
nucleosomes- tiny structure that may help package and fold DNA, regulates the way genes are transcribed
primase (RNA polymerase)- enzyme that synthesizes RNA primer and attaches it to parent DNA strand (template) at
origin of replication
RNA primer- sequence of approximately ten nucleotides that are complementary to the parent DNA, RNA primer is
attached at the origin of replication and allows DNA polymerase to bind to the template strand
continuous and discontinuous synthesis- continuous: deals with the leading strand, discontinuous: way of lagging strand
replication, DNA doesn’t replicate continuously, made by Okazaki fragments
semi conservative model- describes the arrangement of the DNA strands after replication (parent/daughter,
daughter/parent)
purine- two nitrogen bases are larger ex. adenine, guanine
pyrimidine- two nitrogen bases are smaller ex. thymine, cytosine
operon- a group of genes that are expressed together because they have related functions ex. lac genes in E. coli code for
three enzymes that break down lactose
promoter- a region of DNA where RNA polymerase attaches (starting point for transcription)
operator- region of DNA where the repressor attaches (found at the end of the promoter and before the genes)
repressor- a protein that prevents RNA polymerase from attaching to the promoter (prevents transcription)
regulatory gene- DNA that codes for a protein (such as a repressor) that controls the expression of other genes
hox gene- a series of genes that control where tissues and organs develop in the various regions of an embryo ex. fly’s hox
genes where messed with by scientists when the legs starting growing out where the antennas should be and antennas
growing where the legs should be
DNA- deoxyribonucleic acid, polymer, consists of two strands that create a double helix, the nitrogen bases of one strand
form bonds with the nitrogen bases of the other strand, adenine always bonds with thymine, cytosine always bonds with
guanine, DNA is wrapped up into tight coils to be able to fit inside the nucleus of a cell, DNA wraps around special proteins
called histones to form bead-like units of DNA and protein called nucleosomes
speciation: part of macroevolution, making a new species over a long period of time
divergent evolution- similar populations or species evolving in different environments, process in which once-related
populations evolve independently (often because of geographic isolation), two or more related species becoming more and
more dissimilar, evolution in which highly distinct species were once both similar to an ancestral species, presence of
homologous structures in different species is an indication of divergent evolution, ex. polar bear and brown bear, red fox and
kit fox
adaptive radiation- type of divergent evolution in which ancestral species develop into an array of species, each
specialized to fit into a different niche, process by which a species (or small group of species) rapidly evolves into several
different forms, relatively rapid evolution of many diversely adapted species from a common ancestor, ex. Darwin’s finches,
Hawaiian honeycreepers