Topic 11 - Diversity. A plethora of species

Transcription

1 Topic 11 - Diversity A plethora of species

2 What is an animal? Cell differentiation Locomotion Responsive to environment Obtain energy by consuming other organisms

3 Taxonomy: Carolus Linnaeus Swedish Naturalist ( ) System of Classification of organisms ( based on morphology) Modern approach: Domain (3) Kingdom (6) Phylum (35) Class Order Family Genus Species Eukarya Anamalia Chordata Mammalia Primate Hominidae Homo sapiens Eukarya Anamalia Mollusca Cephalopoda Teuthida Architeuthidae Architeuthis dux Eukarya Fungi Basidiomycota Basidiomycetes Agaricales Agaricaceae Agaricus bisporus

4 Species About 1,500,000 species identified Domain Bacteria (5,000?) Domain Archaea (200?) Domain Eukarya Kingdom Protozoa (31,000) Kingdom Plantae (350,000) Kingdom Fungi (69,000) Kingdom Animalia (1,100,000) Sponges Cnidarians Flatworms Roundworms Annelid worms Mollusca Echinoderms Insects 750,000 Other Arthropods Fish 19,000 Amphibians Reptiles 6,000 Birds 9,000 Mammals 4,000

5 Species Estimates: million species on Earth! Insects, bacteria, plants, fungi 1 out of every 5 organisms is a beetle

6 > 100s of new species annually Tube-nosed bat Papua New Guinea Species: 2010 purple octopus Atlantic coast Canada Squid-worm Celebes Sea tiny scaley-eyed gecko Ecuador Snub-nosed monkey Myanmar

7 Discovery of Dinosaurs 1 st discovery: 1822 Iguanodon The Bone War ( ) Montana and Wyoming 150 new dinosaur species O. C. Marsh (Peabody Museum, Yale) Roy Chapman Andrews (American Museum of Natural History, NY) 1923, Gobi desert, Mongolia: First dinosaur nests Edward Cope (Academy of Natural Sciences, Philadelphia)

8 Types of Fossils special97/fightvelopht-l.jpg Replacement/Compression Trace Resin Living Pseudo s/images/castz.jpg s/2007/07/18/coelacanth_3.jpg es/uesc_05_img0260.jpg

9 Fossil Dating Stratigraphy: layers in the rock tell the age Radiometric dating: use of isotopes Index fossil (who is where?): compare to known groups of known ages Together, these methods corroborate one another and give support to dates

10 Burgess Shale Charles Walcott, 1910 Canadian Rockies Sedimentary rock Ancient ocean Contain early complex lifeforms t-si-2.gif

11 Major steps: Sponges Cnidarians Flatworms Simple to Complex Cambrian Explosion (550 million years ago) 21 animal Phyla (body plans) today, 50 during Cambrian! Causes? Ecological changes (habitat, interactions) Oxygenation of atmosphere Evolutionary Arms race

12 The Evolutionary Arms Race Predator- Prey - Predator tries to eat prey, prey tries to escape - Predator evolves a better way to kill prey - only those prey who survive reproduce (prey improve ) - repeat 4 examples Clams Bats & moths Cheetah & Gazelles Humans & bacteria

13 The Evolutionary Arms Race Clams and predators Clams evolved before predators, filled the oceans When predators evolved (rays), they were able to easily eat clams Clams developed defenses burrowing living at the waters edge (Coquina clams) 20,000 species of bivalves (clams, oysters, mussels)

14 The Evolutionary Arms Race Bats and moths Bats use echolocation (sonar) to find moths Some moths evolved ears to hear sonar Some bats avoid sonar and use their ears to listen to moths All bats can still see 140,000 species of moths 900 species bats (most mammals next to rodents)

15 The Evolutionary Arms Race Cheetah-Gazelle Cheetah fastest land animal 70 mph short bursts 0-60 in about 4 seconds 0-68 mph in 3 seconds Gazelle second fastest land animal 50 mph for long periods 13 species Fastest Cheetahs catch the slowest Gazelles Cheetah success = only 20% of time Fastest Gazelles remain to reproduce Cheetahs must get faster Never ending cycle

16 The Evolutionary Arms Race Lewis Carroll s Alice Through the Looking Glass "It takes all the running you can do, to keep in the same place." Red Queen Hypothesis Predators and prey are locked in a never ending cycle of improvement, in which both stay the same AliceThroughTheLookingGlass/pages/036-red-queen-chastisesalice/036-red-queen-chastises-alice-q75-402x500.jpg

17 The Evolutionary Arms Race Humans and microbes Microorganisms (bacteria) infect and kill humans How humans fight bacteria natural ways (immune system) artificial ways antibiotics: > 100 types ex: Penicillin

18 Antibiotic Resistance Antibiotics kill most bacteria by affecting some aspect of bacterial physiology Resistance? Random mutations in bacteria or Improper exposure to antibiotics Those left behind multiply and leave more offspring New population is resistant Multi-drug resistant strains (bacteria develop resistance to many antibiotics) example: Tuberculosis Prevent? Don t: take antibiotics for viruses or the wrong antibiotic (antibiotics are species specific) take them if you don t need them forget to finish the course (leaving individuals can create resistance)

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