Genetic (alleles)

Taxonomic (species, families)

Habitat/Landscape (many measures)

Richness

total number of taxa (whichever one you are looking at)

Assumptions that go along with this:

1 Species identity doesn’t matter (all species are equal)

2 Number of individuals per species doesn’t matter

4 If comparing different areas, similar numbers of individuals have been collected (not the same as same sampling effort)

3 All individuals within each species are equal

Types of Richness

Alpha - number of taxa in local area

Beta - variation in richness between areas

Gamma- number of species in all sites

Diversity

The same as richness, except it DOES take into account variation in numbers

Defining characteristics of Arthropoda

1.) segmentation with regional specialization

2.) jointed appendages

3.)hardened exoskeleton

4.)open circulatory system

5.)tubular alimentary canal w/tubules for execretion

Monophyletic

apomorphy - "advanced"

-recently evolved

pleisiomorphy - "primitive"

Atelocerata

giant subphylums that include centipedes, spiders and scorpions.

Atelocerata

Pauropoda and Symphlya - colorless, small centipedes

Diplopoda - millipedes

Chilopoda - centipedes

Insecta- insects

Arachnida - arachnids 6 pairs of appendages (4 pairs of legs) also has pedipalps and chelicerae

Acari - ticks and mites. unsegmented,

Opiliones- daddy long legs, harvestmen. head and body fused.long thin legs, and predator.

Scorpiones- nocturnal predators, sting, maternal care

Araneae- spiders. solitary, pedipalps, spinnarets

Sclerites

Hardened plates on exoskeleton

serve as protection, to serve oxygen and water transfer, and transfer force of muscles into movement

Sulcus is the suture of these plates- do not line up with muscles inside, allowing for telescoping power!

characteristics of abdomen

11 segments.

8-11 is for reproduction

spirices and cercei

Characteristics of thorax

prothorax = pronotum

enlarged compared to rest of thorax

Mesothorax - 1 pr. of legs, 1 pr. of wings

Metathorax - 1 pr. of legs, maybe 1 pr. of wings

Parts of legs

6 parts of legs -

Coxa

Trochanter

Femur

Tibia(tibial spurs)

Tarsus

Claws

Wing things

1.) hollow veins

2.)contain nerves and hemolymph

3.)muscles in thorax move wings

4.) wings present only in adults

Headparts

Labrum - upper lip, moves longitudinally

Mandibles - "jaws" paired structures that moved at 90 degree angles

Maxillae - paired structures that move at right angles, including palps

Labium- lower lips. moves longitudinally, includes sensory palps.

Eyes- simple or compound eyes. also ocelli- small on head, used for directions, light and dark.

Antennae

used for chemoreception and mechanoreception

Four parts, from base to top: scelrites, scape, pedicel, flagellum.

Antennae types

setaceous- small, short, hairlike and tapered

moniliform - string of beads

filiform- long, threadlike and cylindrical

geniculate- elbowed

plumose- feathery

clubbed- thick at the end.

Parts of exoskeleton

Epidermis - inner living cell that maintains the cuticle

Cuticle - outer, non-living layer made of chitin.

used for waterproofing, protection and structural support.

setae- hairs

epi(wax), exo(hard) and endo(soft) cuticle (from outside)

Simple metamorphosis types

Ametabolous

and

hemimetabolous

Ametabolous- all stages are wingless, only difference is size

hemimetabolous - transition from wingless juvenile to winged adult stage.

imaginal discs

wings develop internally in these structures in complete metamorphosis

Advantages of holometabolous development

adults and juveniles have different niches (less competition)

allows for greater resource speciation

Metamorphosis (8 step process)

1.)PTTH released by brain into hemolymph

2.)PTTH reaches prothoracic gland, stimulates production of ecdysone.

3.) ecdysone stimulates epidermal cells to undergo mitosis, causes molting

4.) epidermal cells secrete enzyme to dissolve cuticle.

5.) epidermal cells lay down new cuticle for next instar (histogenesis).

cuticulin - enzyme resistent layer in new cuticle

6.) apolysis- old cuticle separates from epidermis. includes tracheae and fore and hind guts.

7.) Ecdysis - old cuticle splits off, new instar emerges. the old cuticle is called the "exuvium".

8.)sclerotization : hardening of the new exoskeleton.

Copora Allata

corpora cardiaca

Prothoracis glands

ecdosyne producer

results of classic metamorphosis experiments

1.) brain must trigger something about molting, but is not neurally transmitted

2.) brain triggers something in prothorax -this is the prothoracic gland.

3.) corpora allata controls JH release- transplanting 4th CA into 5th instar will form a new instar before adulthood.

diffusion

movement of materials from high concentration to low concentration

advantages of tracheae

1.) minimizes surface area susceptible to water loss

2.)lined with waterproof cuticle (shed during molting)

3.)Spiricles can be open/closed by muscles

4.)Tracheae are filled with air, and O2 diffuses much faster in air than in water.

Disadvantages of tracheae

1.) diffusion from tracheoles to cells is slow

2.) insects need gas exchange surface of adequate area relative to their volume.

3.) large insects deal with this by ventilation

therefore, this system doesn't work well in low [O2] .

How water insects deal with low concentrations in water

1.) very small, unmodified from terrestrial insects, but spiricles are closed. diffusion of O2 directly through body wall

2.) large aquatic insects have tracheal gills. extensions of body wall loaded with trachea.

different atmosphere specialists

1.) siphon/breathing tube- must be near water surface

2.) "physical gill"  - film of air held on insect body while submerged.little bubbles with O2 diffusing in.

3.) plastron- permanent thin layer of hair left in place, captures some air.

hemoglobin only used in one insect family, found in mudflats

section just behind mouth

musculature acts as a sucking pump

aids haustellate insects

Foregut characteristics

lined with cuticle, able to molt

includes:

1.) esophagus - slender tube moves through peristalsis

2.)crop - a place for temporary storage of food

3.)proventriculus-same function as "gizzard" of birds- lined with "teeth".

4.) valve - regulates food passage to mid gut

Midgut

elongated tube with more surface area- gastric calcae at anterior end.

lined with epithilial cells( not cuticle)

-secrete digestive enzymes

-absorbing nutrients and water

valve regulates passage to hindgut.

Hindgut

final site for absorption of water, salt and any other nutrients

 lined w/cuticle , shed with molt

fat body

amorphous sac of lipid, located in thorax/abdomen

function is energy reserve and hormone secretion

Malpighian Tubules

active transport only

epithelial cells move solutes from hemolymph

increased concentration of salts w/in M.T.

fluid in tubule moves into ileum region of hindgut

Cryptonephridia

tubules bound to hindgut, wrapped in water-impermeable membranes

salt buildup there, encourages osmosis.