multicellular

heterotrophs (rely on other organisms for nourishment

cells lack cell walls

most: ingest food and digest it in an internal cavity

are made of cells organized into tissue

tissue is organized into even more specialized organs

are capable of complex and relatively rapid movement

reproduce sexually, by means of differentiated eggs and sperm

are diploid (cells of adults contain two copies of genetic material)

development characterized by distinctive stages:

a zygote (formed by the product of the first few division of cells following fertilization)

a blastula (hollow ball of cells)

a gastrula (formed when the blastula folds in on itself to form a double-walled structure with an opening to the outside, the blastopore

size ranges from a few cells to organisms weighing many tons

inhabit the sea, fresh water or land

The Black Horse Fly belongs to the

bilateral symmetry

strongly segmented body

protostomes (coelom formed by schizocoely)

open circulatory system with: heart, arteries and body sinuses called hemocoel

body covered by exoskeleton (cuticle made of protein and chitin)

gut is complete

well-developed sensory organs at anterior end, extensive cephalization

gas exchange takes place through the body surface using: gills, tracheae (chitinized tubes), spiracles (openings to outside), book lungs

The Cattle Egret belongs to the

Phylum Chordata

bilateral symmetry

segmented body, including segmented muscles

deuterostomes (three germ layers and a well developed coelom)

ventral heart, dorsal and ventral blood vessels and a closed blood system

bony or cartilaginous endoskeleton usually present

complete digestive system

Four anatomical structures that are present at some stage during the organism’s life:

1.a notochord: a rod that extends the length of their body and lies dorsal to the gut but ventral to the central nervous system

stiffens the body and acts as support during locomotion

2.single, dorsal, hollow nerve chord, usually with an enlarged anterior end (brain) 3.tail projecting beyond anus

4.pharyngeal slits

The Black Horse Fly belongs to the

Class Insecta

tracheal system for "breathing" with tracheae and spiracles

mouthparts: variable and related to eating, may include mandibles, maxillae,etc.

exoskeleton

body has three divisions (tag- mata): head, thorax, abdomen

nitrogenous waste excreted through Malpighian tubules

fertilization is internal

may have compound eyes or simple eyes or both

dioecious

pair of antennae

three pairs of walking legs

complete and complex digestive tract

complex nervous system

sense organs complex and complete

mating varied

The Cattle Egret belongs to the

Class Aves

"one-way" breathing system

horny beak, no teeth

strong, lightweight skeleton

large muscular stomach

excretes uric acid (in solid white crystals), lacks bladder

feathers (highly modified scales)

amniotes

large eyes

dioecious

body adapted for flight

The Black Horse Fly belongs to the

found in all habitats

only one pair of normal wings, secondary "remnant" wings called halteres that may stabilize flight

large compound eyes

mouthparts modified for piercing, lapping or sucking fluids

antennae of some kind

undergo complete metamorphosis

larvae called maggots: soft, legless, headless, live in soil, decaying material or as parasites

The Cattle Egret belongs to the

Order Ardeiformes

The Black Horse Fly belongs to the

Family Tabanidae

stout, broad-headed flies

3/8" - 1 1/8" long

bulging, sometimes brightly colored eyes

flight can be silent

females bite

males feed on nectar and pollen

adults live around water

larvae live in shallow water or moist soil

The Cattle Egret belongs to the

Family Ardeidae

long legs, long, staight bill, long neck, short tail, feet unwebbed

neck usually held in s-curve in flight, wings flap evenly

stalk and eat fish

wading birds of all wetlands

sexes look and act alike in rituals and parenting

3/4-1 1/8"

mainly black in color

wings unpatterned

larva white with black bands

lives in meadows, open grasslands, marshy areas or near slow streams

range includes Quebec south to Florida, the Gulf States ...west to New Mexico, and north to the Pacific Northwest

females bite (slice skin of victim with bladelike mouthparts) and suck blood from large mammals includ- ing cattle, horses, etc.

males suck nectar

larva eats small aquatic insects

20"

small white heron, makes croaking noises, very social

lives in marshes or pastures, roost and breed in wooded areas of marshes

range is greatly expanded: includes Old World tropics, Florida, California, much of southern U. S. and as far north as southern Canada

can be seen perched on the backs of cattle, catching insects

References:

www.ucmp.berkeley.edu (arthropoda, insects, vertebrates)

www3.ncbi.nlm.nih.gov/htbin-post/Taxonomy (black horsefly, cattle egret)

www.nmnh.si.edu/entomology/Diptera

www.oit.itd.umich.edu/bio108 (Animalia, Arthropoda, Insecta, Uniramia, Chordata, Vertebrata, Reptilia, Aves)

Insects and Spiders, Alfred A. Knopf, New York, 1995.

The Audubon Society Field Guide to North American Birds: Western Region, Alfred A. Knopf, New York, 1977.