BIO Lab final

Phenotype

Long or short bill

In H-W equation phenotype frequencies would be p2 + 2pq (long bill) and q2 (short bill) respectively

Genotype

LL, Ll, ll

In H-W equation genotype frequencies would be p2, 2pq and q2 respectively

Allele

L or I

In H-W equation allele frequencies would be p and q respectively

Natural selection

Those individuals with advantageous traits survive better and therefore live to reproduce more, passing
those traits on to the next generation.

These traits exist BEFORE the selection occurs

Genetic drift

Random change in allele frequencies and thus the traits they encode. Can result from random mating if population becomes small (population bottleneck)

Founder effect

A type of genetic drift, in which a new population is founded in a geographically
distinct region.

Monophyletic

Includes common ancestor and ALL its descendants. So every branch that arises from the
common ancestor must lead to species that are part of the group in question.

Paraphyletic

includes common ancestor and but NOT all its descendants. So some branch that arises from the
common ancestor will lead to species that are NOT part of the group in question

Polyphyletic

does not include common ancestor. This will usually be a group that is centered around a trait
that evolved separately (did not come from a common ancestor)

Derived Character

a trait found in a group that is not found in their ancestral group

Homoplasy

a character trait shared between two groups that is NOT inherited from their common ancestor.

Synapomorphy

a trait that is derived from the most recent common ancestor. Found in all its descendants.

PHYLUM PORIFERA

Sponges
No true tissues or organs, pore-bearing

PHYLUM CNIDARIA

Jellyfish, corals, anemones

Radial

tentacles with stinging cells called nematocysts

PHYLUM PLATYHELMINTHES

Flatworms (planaria, tapeworm...)

Bilateral

Dorso-ventrally flattened worms

PHYLUM NEMATODA

Roundworms – (C. elegans, Ascaris)

Bilateral

Smooth, round-bodied worms with tapered ends

PHYLUM ANNELIDA

Segmented worms (earthworms, leeches...)

Bilateral

PHYLUM MOLLUSCA

Clams, mussels, squid, octopus, snails, slugs...

Bilateral

Mantle, muscular foot

PHYLUM ARTHROPODA

Insects, spiders, scorpions, lobster, crab, shrimp…

Bilateral

Jointed appendages, chitinous exoskeleton

PHYLUM ECHINODERMATA

Sea stars, sea urchins, sea cucumbers...

Bilateral & secondary pentaradial

Cephalochordata (invertebrates)

lancelets

notochord extend to front of head

Tunicata (invertebrates)

Tunicates (sea squirts)

Tough outer covering or tunic

pharyngeal slits only

Agnatha

Jawless fish (lamprey, hagfish)
jawless fish

Chondrichthyes

Cartilaginous fish (sharks, skates, rays)

Fish with skeleton made of cartilage

pharyngeal slits (gills), dorsal nerve cord, post-anal tail,
a few have notochord but most do not

Osteichthyes

Bony fish

fish with skeleton made of bone

pharyngeal slits (gills), dorsal nerve cord, post-anal tail

Amphibia

Frogs, salamanders...

incompletely adapted to life on land
Respire at least partially through their skin

dorsal nerve cord, post-anal tail (many)
A few have gills as adults, but most do not

Reptilia

Snakes, crocodiles, turtles

completely adapted to life on land, amniotic egg, scaly skin

dorsal nerve cord, post-anal tail

Aves

Birds

feathers, beaks

dorsal nerve cord, post-anal tail

Mammalia

Horse, cow, cats, humans, etc.

hair, mammary glands

dorsal nerve cord, post-anal tail (in most)

Exponential

growth continues indefinitely
Not usually seen in nature
Graph does not level off
Population increases exponentially

Logistic

Common in nature
Graph looks sigmoidal (S-shaped)
Plateau is at carrying capacity
Environmental resistance causes curve to
level off

Density-dependent

only affect population growth when the population is large. This is the type of factor causing the environmental resistance (leveling off) in the logistic curve above. The curve is unaffected at low populations (starts off looking exponential) but when the population gets large growth is affected.
often necessary resources, such as food and water. When population is low there is plenty, but become limiting when population is large

Density-independent

affect population growth even when population is small
natural disasters, etc.

Lincoln-Petersen

𝐍 = (𝐌 ∗ 𝐂)/𝐑

N = the population estimate
M = number of animals marked in first capture
C = number of animals in recapture
R = marked animals in recapture

Schnabel

Mi = number of previously marked animals at capture i
Ci = number of animals captured at capture i
Ri = previously marked animals captured at capture i

Tragedy of the commons

If a resource is open access (freely available for people to use in an unregulated way) it will eventually be destroyed.

Stream biodiversity simulation

Pollution had no effect on the total number of invertebrates caught
Pollution decreased the number of different species caught
Thus, biodiversity (variety of life) in the stream decreased

Plant biodiversity simulation

Certain types of plan thrived in the dry (xeric) environment while others did better in the moist (mesic) environment.

Notochord

a flexible skeletal rod that runs lengthwise through the animal closer to the dorsal (back) side. It is made a material similar to cartilage

Dorsal nerve cord

a hollow tubular chord of nervous tissue running lengthwise through the animal usually dorsal to the notochord

Pharyngeal slits

a series of parallel slits in the pharynx. They are modified into various structures in different chordates, for example gills in fish

Post-anal tail

a tail that extends posteriorly from the location of the anus

1. Cardiac stomach

2. Digestive gland

3. Heart

4. Gills

label numbers

1. Green gland

2. Brain

3. Ventral nerve cord

4. Nerve cords

label numbers

1. gills

2. air bladder

3. trunk muscles

4. ribs

5. heart

6. liver

7. pyloric ceaca

8. stomach

9. intestine

10. gonad

label numbers