Kingdom Animalia Characteristics of the Animal Kingdom Over 2 Million Species Eukaryotic Heterotrophic Multicellular No Cell Walls General Classification Invertebrates – animals that do not have a backbone • Compose 95-97% of the animal kingdom • Include animals such as Sponges, Jellyfish, Worms, Snails, Clams, Squids, Spiders, Insects, Sea Stars, and many more General Classification Vertebrates – animals that do have a backbone • Compose 3-5% of the Animal Kingdom • Include animals such as Reptiles, Amphibians, Mammals, Fish, and Birds Cell Specialization Considering that animals are multicellular, they have cells with specialized functions! • Levels of Organization Cells (enveloped by a cell membrane) Tissues (groups of similar cells) Organs (2-4 types of tissues) Organ Systems (composed of many organs) Organ Systems • Animals come in many shapes and sizes. • The complexity of organ systems from one animal to the next can vary greatly! • Each animal must have a way to complete the following functions: Feeding, Respiration, Circulation, Excretion, Response, Movement, and Reproduction FEEDING • Some animals have mouths (i.e., humans) to assist in feeding where as others are filter feeders and absorb nutrients from the water around them (i.e., sponges) • Some animals therefore have a very developed digestive system whereas others do not. • However they get food, all animals are heterotrophic and need nutrients for energy! FEEDING • Herbivores eat plants • Carnivores eat other animals • Omnivores eat plants and animals FEEDING • Filter feeders strain organisms from the water • Detritivores feed on detritus (dead organic matter) • Some animals form symbiotic relationships RESPIRATION • Some animals have a very developed respiratory system that includes a trachea (windpipe) and lungs. Others simply absorb oxygen through their skin from the environment CIRCULATION • Not all animals have blood and extensive circulatory systems. • The main functions of the circulatory system are to transport nutrients and oxygen to the cells and carry waste away. • For those simple animals that can transport oxygen, nutrients, and waste by diffusion, a developed system is not necessary EXCRETION • A primary waste product of cellular metabolism is ammonia, a poisonous substance that contains nitrogen • Ammonia must be eliminated from the body • Humans use kidneys to rid the body of ammonia waste in urine. Other organisms mix ammonia with feces or allow the ammonia to diffuse into the surrounding water RESPONSE • Every animal must respond to the environment. Some are able to respond more quickly and dramatically than others, depending on the complexity of their nervous system • Some animals have only have a few nerve cells while others have brains • Cephalization – concentration of sense organs at the front of an animals body MOVEMENT • Some animals are sessile • Most animals can move from place to place • Movement also includes the forcible movement of particles within an animal during such processes as digestion and circulation • Animals are the only kingdom that have muscles REPRODUCTION • Most animals produce sexually by the production of gametes. This maintains genetic diversity. • Many also reproduce asexually. BODY SYMMETRY • Radial Symmetry • Bilateral Symmetry Charles Darwin’s Theory of Evolution How does evolution occur? Step 1: Organisms vary Charles Darwin’s Theory of Evolution How does evolution occur? Step 2: Varied organisms compete over scarce resources Charles Darwin’s Theory of Evolution How does evolution occur? Step 3: Certain variations survive & reproduce; • Step 3: Certain variations survive and Adaptations are passed on through the population reproduce Charles Darwin’s Theory of Evolution How does evolution occur? • Step 4: Adapted populations become geographically isolated & form subspecies Arizona Coues Deer Minnesota Whitetail Deer Charles Darwin’s Theory of Evolution How does evolution occur? • Step 5: Subspecies may eventually form separate species Blacktail Deer Whitetail Deer Mule Deer Charles Darwin’s Theory of Evolution Darwin’s background Born in 1809 in England Tried medical school (Edinburgh) Switched to theology school (Cambridge) Joined the crew of the HMS Beagle Charles Darwin’s Theory of Evolution Darwin’s background Set sail in 1831: voyage around the world Numerous observations, enormous collections Led him to propose a revolutionary theory Charles Darwin’s Theory of Evolution Why revolutionary? Europeans in Darwin’s day Earth was only a few thousand years old Neither Earth nor life had changed (robins had not changed) Charles Darwin’s Theory of Evolution Cape Verde Islands Found a band of white sea shells in a cliff Band was 40 ft. above sea level ? How did marine organisms get above sea ? level? Charles Darwin’s Theory of Evolution Rio de Janeiro, Brazil Explored rainforest about 100 miles up coast Collected 68 beetle species in one day ? How did such amazing diversity arise? Charles Darwin’s Theory of Evolution Punta Alta, Argentina Found a giant, rodent-like fossil Unknown at the time, later named Toxodon ? What caused its extinction? Charles Darwin’s Theory of Evolution Punta Alta, Argentina Found a giant, fossil ground sloth Unknown at the time, later named Megatherium ? What caused its extinction? Charles Darwin’s Theory of Evolution Buenos Aries, Argentina Found a giant, fossil armadillo Unknown at the time, later named Glyptodon ? What caused its extinction? Charles Darwin’s Theory of Evolution St. Fe Bajada , Argentina Found a large molar tooth Later identified as a mastodon tooth ? How can South American and European species be so similar? Charles Darwin’s Theory of Evolution Valdivia, Chile Witnessed an earthquake Noted that marine rock rose a few feet above sea level ? Can land rise up slowly over long expanses of time? Charles Darwin’s Theory of Evolution Villa Vicencio, Chile 6000 feet above sea level 700 miles from the coast Mountains formed of submarine lava flows ? How long ago was this land underwater? Charles Darwin’s Theory of Evolution The Galapagos Islands Volcanic islands 600 miles west of S.A. Close together but different climates Smaller islands: hot, dry, barren Larger islands: wetter, more diverse Charles Darwin’s Theory of Evolution The Galapagos Islands Noted several brown, ordinary birds Noted diversity in beaks and feeding habits Did not realize they were all finches Charles Darwin’s Theory of Evolution The Galapagos Islands Later hypothesized common ancestry Known today as adaptive radiation Charles Darwin’s Theory of Evolution The Galapagos Islands Noted similarity of very different organisms: penguins, fish, and porpoises Known today as convergent evolution Charles Darwin’s Theory of Evolution Emu Ferry, Australia Astonished by Australian creatures Particularly the platypus ? Why are Australian animals so unique? Charles Darwin’s Theory of Evolution Keeling Islands Noted islands were composed entirely of coral ? Did a coral reef grow on an ancient volcano? Charles Darwin’s Theory of Evolution Madagascar Examined an orchid Nectar at the tip of a 40 cm long spur ? Is there a pollinator with a 40 cm tongue? Charles Darwin’s Theory of Evolution Madagascar Hypothesis later confirmed Example of coevolution Charles Darwin’s Theory of Evolution On the Origin of Species Brought back specimens from around world Began writing: diversity and evolution Did not rush! Ideas challenged thought of the day Charles Darwin’s Theory of Evolution On the Origin of Species Finally published in 1859 Mechanism: natural selection Some thought it brilliant! Others were very opposed