The Hong Kong University of Science and Technology Department of Biology http://www.ust.hk http://www.ust.hk/~webbo/ Presenters : Arthur Cheung (bo_cklab@stu.ust.hk Louis Shum (bo_sht@stu.ust.hk) What Is Adaptation? Adaptation: • An inherited trait or set of traits that increases the chances of survival and reproduction of an organism in a particular environment. • In different habitats, each species has its own set of characters for survival. What Is Adaptation? • Natural Selection = Survival of the fittest + Selective Pressure (Charles Darwin, Origin of Species, 1859) • Sexual selection (性選擇) • Ecological selection (生態選擇) Harsh Habitats in Our Biosphere • South Poles (南極) • Tropical Rain Forest (熱帶雨林) • Desert (沙漠) • Hydrothermal Vent (熱泉) http://www.learninglive.co.uk/srbprojects/internet/pages/habitat%20adaptation/webpages/habitatindex.html South Poles (南極) • Temperature: -40oC in average, can be as low as -57oC • Winds: up to 100 mph http://eosl.csl.uiuc.edu/home/images/SP/SouthPole_ Station%5B1%5D.jpg http://www.mreclipse.com/Store/LM1/image/LM101w.JPG Tropical Rain Forest (熱帶雨林) • Rainfall: 250-1000cm/ year • Temperature: ~35oC • Climate: Hot and wet http://www.blueplanetbiomes.org/rai nforest.htm Desert (沙漠) • Rainfall: <25cm/year • Temperature: >40oC in daytime • Climate: Hot and dry http://bama.ua.edu/~liu025/photo/China%20 Phote/TengGeli%20Desert.JPG http://midsun.uwaterloo.ca/images/msvi /asc/Desert.jpg Hydrothermal Vents (熱泉) • Temperature: 390oC • High hydrogen sulfide (H2S) and methane (CH4): food sources of some organisms • Geo-chemical energy http://statusreports-atp.nist.gov/reports/images/deep-sea.jpg Case Study: Penguin (企鵝) Reasons for choosing this model: • Can be found in extreme environments (e.g. South Pole) and in other habitats (e.g. South Africa) • Penguins in different habitats have different adaptation characteristics • Video: http://www.nationalgeographic.com/channel/hig hspeed/2004/08/20040823news.html?format=w m&vid=20040823ngppenguins.asf Evolution of Penguins Phylogenetic Tree http://www.adelie.pwp.blueyonder.co.uk/Evolution/evolve.html What Problems Do Penguins Face? - Abiotic Factors (非生物性因素) - Biotic Factors (生物性因素) Abiotic Factors (非生物性因素) • Non-living factors affecting the life of organisms – Light – Temperature – Atmospheric gases South Pole: • Temperature: -40oC in average, can be as low as -57oC • Winds: Strong winds up to 100 mph Biotic Factors (生物性因素) • Environmental influences resulting from the activities of living organisms – Competition (競爭) • Interspecific competition (種間競爭) • Intraspecific competition(種內競爭) – Predation (捕食) Predation Penguins are preys of: • Leopard seals (海豹) • Killer whales (殺人鯨) • Sharks (鯊魚) Leopard Seals http://www.dougallan.pwp.blueyonder.co.uk/picpops/images/lectures_da15.jpg Killer Whales http://menua.aic.net/~vvk/seaa/orc/orca11.jpg Sharks http://www.laups.org/cgray/images/blue.jpg http://seashadows.narod.ru/rus/images/im020.jpg How Do Penguins Adapt to the Environment? http://www.adelie.pwp.blueyonder.co.uk/PhotoIndex/SPH_PICS.htm Adaptation of Penguins (1) Morphological (形態上) (2) Physiological (生理上) (3) Behavioral (行為上) (1) Morphological Adaptation • Feather • Bone • Different colors in dorsal and ventral parts of the body Which Feather Belongs to Penguin? http://wings.avkids.com/Book/Animals/inte rmediate/birds-01.html http://www.seaworld.org/infobooks/ Penguins/physical.html Feather • 4 layers of feathers • Shiny feathers uniformly overlap to cover the skin • Highly specialized: short, broad, and closely spaced • Tufts of down on the feather shafts: insulation (隔熱) Which Skeleton Design Makes Penguin a Good Diver? http://octopus.gma.org/su rfing/antarctica/penguin.h tml http://www.adelie.p wp.blueyonder.co.u k/anatomon.htm http://192.107.108.5 6/portfolios/h/harris _d/final/sectns.htm Different Colors in Dorsal and Ventral Parts • Ventral part(腹部): White • Dorsal part (背部): Black Why different colors in dorsal and ventral parts? (2) Physiological Adaptation Characteristics unique in South Pole species: • Recycle of body heat • Mechanism of diving • Preservation of food Recycle of Body Heat http://www.biology.ualberta.ca/courses.hp/bio366/Image71.jpg Mechanism of Diving http://www.bio.davidson.edu/people/mid orcas/animalphysiology/websites/2004/G ooch/index.htm http://www.biology.ualberta.ca/c ourses.hp/bio366/Image71.jpg Mechanism of Diving • • The most important mechanism involved in diving is oxygen saving. Reduced heart rate Change in blood flow (by-passing) and reduced sensitivity to CO2 Reduced Heart Rate http://www.bio.davidson.edu/people/midorcas/animalphysiology/websites/2004/Gooch /oxygen.htm#adl Change in Blood Flow and Reduced Sensitivity to CO2 • Increased oxygen supply to skeletal muscle • Reduced blood flow to brain, heart and lungs • Prevent termination of breathing – Reduce receptors’ sensitivity in brain to CO2 Preservation of Food Proteins in stomach for preservation of food • Antimicrobial peptides – Example: β-defensins (Sugiarto et al., 2004 ) • Spheniscins (Landon et al., 2004) – Work with other antimicrobial peptides – Preserve food for several weeks during incubation of eggs (3) Behavioral Adaptation Characteristics unique in South Pole species: • Huddling • Drawing neck and flipper tightly against the body • Sharing parental duties Why Do Penguins Form Colonies in Winters? http://www.aad.gov.au/default.asp?casid=3524 Huddling • Density: 10 individuals per m2 • Reduces heat loss up to 50% – Temperature inside the huddle can be as high as 35oC • Prolongs fat storage Huddling In windy days, individuals at the edge are exposed to the wind and therefore have a higher rate of heat loss. • They shift from edge to center to keep their bodies warm. • They move together with their chicks. Neck and Flipper Drawn Tightly against Body • Why do penguins always draw their neck and flipper tightly against the body? – Minimize surface area contact with the surrounding – Reduce heat loss http://englishnf.pinguins.info/ Sharing Parental Duties • Emperor Penguins (Aptenodytes forsteri) incubate eggs without eating for 65 days • Females search for food and help in incubation – How can females find their partners? • They recognize their partners by voice http://www.antarcticconnection.com/antarctic/wildlife/penguins/a delie.shtml Penguins’ call Sharing Parental Duties • Parents can stop eating in turn for more than 3 months to take care of the chicks • Feeding chicks with fish and squid by regurgitation Sharing Parental Duties http://www.aad.gov.au/default.asp?c asid=3524 http://www.aad.gov.au/default.asp?casid=3524 Summary • Purpose of adaptation: Increases the chances of survival and reproduction of an organism in a particular environment. • Forms of adaptation: Morphological, physiological, behavioral • Case study: Penguins – Characteristics found in South Pole species different from those in South Africa Major References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Akwarium Gdynskie, http://www.aad.gov.au/default.asp?casid=3524 Animal, http://wings.avkids.com/Book/Animals/intermediate/birds-01.html Animal explore discover connect, http://www.seaworld.org/infobooks/Penguins/physical.html Animal diversity web, http://animaldiversity.ummz.umich.edu/site/accounts/information/Sphenisciform es.html Antarctic connection, http://www.antarcticconnection.com/antarctic/wildlife/penguins/adelie.shtml Australian Antarctic Division, http://www.aad.gov.au/default.asp?casid=3524 BBC weather center, http://www.bbc.co.uk/weather/features/weatherbasics/zones_desert.shtml Boreal Ecology, http://www.biology.ualberta.ca/courses.hp/bio366/Image71.jpg Charles Darwin, The Origin of species, Modern Library. P.108-117 Diving mechanism in Penguins, http://www.bio.davidson.edu/people/midorcas/animalphysiology/websites/2004/ Gooch/oxygen.htm#adl Major References 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. Landon C, Thouzeau C, Labbe H, Bulet P, Vovelle F (2004). Solution structure of spheniscin, a beta-defensin from the penguin stomach. J Biol Chem. 2004 Jul 16;279(29):30433-9 Paul and Bernice Noll's Window on the World, http://www.paulnoll.com/Oregon/Birds/Avian-Skeleton.html Penguins around the world, http://www.siec.k12.in.us/~west/proj/penguins/species.html Pete & Barb’s Penguin Pages, http://www.adelie.pwp.blueyonder.co.uk/anatomon.htm Rezende EL, Swanson DL, Novoa FF, Bozinovic F (2001) Passerines versus nonpasserines: so far, no statistical differences in the scaling of avian energetics. The journal of Experimental Biology 205, 101-107 (2002) Sugiarto H., Yu PL (2004), Avian antimicrobial peptides: the defense role of βdefensins. Biochemical and Biophysical Research Communication 323 (2004) 721-727 Tropical Rain forest, http://www.blueplanetbiomes.org/rainforest.htm The climate of tropical rain forest, http://www.cdli.ca/CITE/rainforest_climate_students.htm Wikipedia, http://en.wikipedia.org/wiki/Ecological_selection World Habitat, http://www.learninglive.co.uk/srbprojects/internet/pages/habitat%20adaptation/webpages/habitatindex.html Enjoy the nature Acknowledgements • • • • • • • • • • Prof. K.L. CHOW Prof. Philip I.K. SOU Prof. Michael K.Y. WONG Dr. T.K. GOH Dr. Maggie LI Dr. Ice KO Dr. Y.Y. REN Mr. Wilfred LEUNG Mr. Jack LI Center for Enhanced Learning and Teaching This project is funded by the Center for Enhanced Learning and Teaching of HKUST.