Photo Credit: Photograph by Chris Newbert/Minden Pictures Unit 19 Invertebrate Animals

Photo Credit: Photograph by Chris Newbert/Minden Pictures Introduction In this unit we will introduce characteristics of Kingdom Animalia and focus on invertebrate animals (that lack a backbone).

Characteristics of Animals Eukaryotic; their cells have a nucleus w/ specialized organelles Cells DO NOT have cell walls Multicellular Heterotrophs; animals cannot make their own food

Characteristics of Animals Cont. Feeding/Excretion Support/Movement Respiration/ Circulation Response to Environment Reproduction All to maintain - Homeostasis s/schools-fish/school-of-grunt-fish-photography.html

Homeostasis Homeostasis is the process by which animals maintain a fairly stable internal environment. Organisms require a set of constants for survival. 4-f1.2.jpg

Feeding and Excretion Animals must find, consume, and digest food for energy. They must also get rid of waste products. Just as the machines in a factory produce waste, the cells of organisms often produce a “trash” substance called ammonia which is poisonous. The excretion (to get rid of) of wastes from the body varies between organisms. creatures/pygmy-seahorse-doubilet.html

Most animals are active and require energy for movement. Some animals are sessile, or permanently attached to one spot (EX sponges). Most animals are motile and are free-moving at some time in their life cycle (which allows offspring to settle in a new place). Some animals are passive and move only when carried by another force such as water currents or wind. erwater-scenes/basket-sea-star-photography.html Support & Movement

Respiration & Circulation Animals must have oxygen to release energy within cells. Some animals use lungs while some aquatic animals use gills to bring in oxygen and get rid of the CO2 by product of cellular activity. Others use diffusion to pass the gases in and out of their body.

Response Animals must be aware of their environment to obtain food, seek protection from predators, find mates and reproduce, etc. Animals respond to their environment using specialized nerve cells to sense external stimuli (light, sound, etc) and to process information. EX The shark using senses. graphy/photo-of-the-day/shark-kingman-reef- pod.html

Reproduction Animals must reproduce to maintain the species. Most reproduce sexually using sperm and an egg. Some can reproduce asexually (from just one parent).

Animal Body Symmetry Asymmetry – lack of symmetry (EX sponge). Radial symmetry – circular arrangement around a central point (EX sea star). Bilateral symmetry – arrangement along a middle plane (EX human). abee/biobk/bodysymm.gif

Review of Taxonomy There are nine categories of taxonomy and all living things are sorted by their genetic relationships and characteristics they possess. Species [the most specific]GenusFamilyOrderClassPhylumKingdomDomain [the most general]

Domain Eukarya Kingdom Animalia Phylum Porifera TxBkRef pg AKA Sponges are the oldest and simplest and probably most unusual animals.  Name means “pore-bearer”  Sponges are sessile and do not move (as adults).

Sponge Cont.  No symmetry (asymmetry)  Sponges lack special tissues  They have structures that pump water through their body to respire and filter food, and excrete waste.  Sponge Video Sponge Video

Sponge Photos 20with%20Sponge%20Coral%20Belize%20Barrier%20Reef_Image%20Copyright%202009%20- %20Tony%20Rath%20of%20Tony%20Rath%20Photography%20www.tonyrath.com.jpg

Domain Eukarya Kingdom Animalia Phylum Cnidaria TxBkRef pg Think floating jellyfish and anemones!  Found all over the world, cnidarians (C is silent) are soft bodied, carnivorous animals with stinging tentacles.  Some are sessile, some motile (they move)

Cnidarians Cont.  Radial symmetry  Cnidocytes – unique cells on the tentacles that contain stinging, poisonous barbs to capture prey  Cnidarians make up the world’s coral reefs kvisioncentre/Images/Underwater- Realm-2.jpg ds/720467/png/screen-capture-2.png

Cnidarians Photos

Photos Cont. gequest3d.com /photos/combje llies/index.htm  Jellyfish Video Jellyfish Video

Domain Eukarya Kingdom Animalia Phylum Platyhelminthes TxBk Ref pg AKA Flatworms are un- segmented (no rings) and appear flat, most only a few millimeters thick.  They move to obtain food and escape predators.  Bilateral symmetry, and cephalization (a head region)

Flatworm Cont.  They have a single digestive opening, a mouth/anus in which food enters and undigested waste leaves.  Do not need a circulatory or respiratory system to transport materials, but use diffusion.

Flatworms Cont.  They can be both carnivorous or parasitic (EX tapeworms can live inside the human intestines).  Flatworm Video 1 Flatworm Video 1  Flatworm Video 2 Flatworm Video 2

Domain Eukarya Kingdom Animalia Phylum Nematoda TxBkRef pg AKA Roundworms, are unsegmented worms that can be microscopic or a meter!  Most roundworms are free moving and are found in the soil or water; many are parasites that live in plants and animals.  Bilateral symmetry ms_RoseRibbonWorm_90p_P jpg

Roundworms Cont.  Humans can be infected with roundworms such as Ascaris lumbricoides which causes Ascariasis [affecting 1.3 billion people worldwide].  Roundworm parasites can be spread through contaminated produce, unwashed hands, and raw fish.  Roundworm Video Roundworm Video

Roundworms Photos With over 250,000 known cases across the United States, canine heartworm disease continues to plague our pets.

Domain Eukarya Kingdom Animalia Phylum Annelida TxBkRef pg Think earthworms and leeches!  AKA worms with segmented bodies  The name means “little rings”.

Segmented Worms Cont.  Most are free moving and are found in the soil as decomposers or in water.  Bilateral symmetry  Have fully formed organ systems with a simple brain, nerves, heart and blood vessels, etc.  Worm Video 1 Worm Video 1  Worm Video 2 Worm Video 2

Annelid Photos thumbnail/ehow/images/a08/7n/4n/annelid- worms-800x800.jpg

Domain Eukarya Kingdom Animalia Phylum Mollusca TxBkRef pg Think snails, clams, and the octopus!  Characterized by soft bodies that is sometimes with a shell.  Bilateral symmetry  Have fully formed organ systems

Some Classes of Mollusks  Class Gastropoda (mollusks with shells; EX snails)  Snail Video Snail Video snail.jpg?w=600

Some Classes of Mollusks Cont.  Class Bivalva (mollusks with a hinged shell; EX clams and oysters)  Clam Video Clam Video

Some Classes of Mollusks Cont.  Class Cephalopoda (most advanced, intelligent mollusks; EX nautilus, squid, octopus Ink to confuse predators Can manipulate skin colors Tentacles to attack prey  Octopus Video Octopus Video  Squid Video Squid Video

Mollusks Photos ge/images/octupus.jpg

Domain Eukarya Kingdom Animalia Phylum Echinodermata TxBkRef pg Think sea stars, sand dollars, and sea urchins!  Means "spiny skin“ and these organisms live only in the ocean.  Radial symmetry  Have fully formed organ systems  Echinoderms have the ability to regenerate their limbs.  Echinoderm Video 1 Echinoderm Video 1  Echinoderm Video 2 Echinoderm Video 2

Echinoderms Photos These are the elaborate filter- feeding tentacles of a Sea Apple. purpuratus/image-G69185.html

Echinoderms Photos Cont.

Domain Eukarya Kingdom Animalia Phylum Arthropoda TxBkRef pg Think butterflies, shrimp, and spiders!  Means “jointed feet”  Bilateral symmetry  Have fully formed organ systems Sensing antennae for sound, odor too Well developed eyes umb/9/99/150px-Zorak-Mantis.png

Arthropods Cont.  They have segmented bodies fused into larger body regions.  Exoskeleton - made of chitin; is a hard covering outside of body for support and protection  Molting –; shedding of old exoskeleton required for an arthropod to grow  Arthropod Video Arthropod Video et/Images/Lobster.jpg

Some Classes of Arthropods  Class Arachnida –have four pairs of walking legs, chewing mouthparts, and two body segments; EX spiders, ticks, and scorpions  Spider Video Spider Video widow-spider/?source=A-to-Z

Sun Spider Mouth Close Up ImageImage

Some Classes of Arthropods Cont.  Class Crustacea – chewing mouthparts, two pair of antennae, and two body segments typically with five legs with clawsc; EX shrimp, crabs  Crab Video Crab Video 4/shrimp.jpg

Some Classes of Arthropods Cont.  Class Insecta– have mouthparts, most have compound eyes, antennae and three body segments with six legs; EX grasshoppers, flies, and beetles weevils_10-coolest-insects.jpg G html

Ants lovingly nurture various kinds of true bugs (Hemiptera), often stroking them gently and protecting them from predators and parasites. The bugs reward the ants with sugary nectar in the form of honeydew that they secrete as a waste product from feeding on the sap of the plants. These are scale insects (the red blobs) being tended by redheaded cocktail ants in Kenya. In many ways this relationship is similar to humans keeping cattle or other livestock and milking them. Photograph by Dino Martins National Geographic

The Evolution of Invertebrates Fossil evidence shows that the first animals [sponges – shown to the right] evolved from Protists with flagella about 650 million years ago.  Sponge Video Sponge Video The second group to evolve were Cnidarians; but because they are soft bodied, they do not fossilize well [estimates are about 630 million years ago] /Fossils-Namibia-worlds-oldest- animal-life--oldest-ancestor-sponge-760- million-years-ago.html

This fossil jellyfish shows similarity to the modern jellyfish, Cunina (right). It was one of four different types of jellyfish dated back to the Cambrian by researchers in These ancient jellyfish showed the same complexity as modern jellyfish, meaning they either developed rapidly 500 million years ago, or today’s varieties are much older. ImageImage

Invertebrate Evolution Cont. Flat and roundworms are thought to have evolved next, but their soft bodies make it hard to find fossil evidence. Segmented worms [annelids] evolved first in the sea, about 540 million years ago. se-Lagerstatt/Annelida/Annelidab.htm Explosion/Annelid2/aworm.htm

Invertebrate Evolution Cont. Mollusks evolved next, about 500 million years ago – many types of shelled mollusks, like the nautilus, were found in the early oceans of Earth.  A fossilized nautilus [left], the modern [right]  Nautilus Video Nautilus Video

Invertebrate Evolution Cont. Arthropods evolved about 500 million years ago; they began in the seas, like their early ancestor, the trilobite [see image, extinct for 248 million years]. Arthropods became the first land animals, circa 300 million years ago.  Arthropod Video Arthropod Video hanrhart_Formation,_Jbel_Gara_el_Zguilma,_Draa_Valley,_Morocco_- _Houston_Museum_of_Natural_Science_-_DSC01584.JPG

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Invertebrate Evolution Cont. Echinoderms are considered the group most closely connected to chordates; they first appeared in the fossil record about 540 million years ago. Echinoderms and chordates both develop similarly after fertilization [they are deuterostomes].