Transcript What Is Adaptation? - Department of Physics

The Hong Kong University of
Science and Technology
Department of Biology
http://www.ust.hk
http://www.ust.hk/~webbo/
Presenters :
Arthur Cheung ([email protected]
Louis Shum
([email protected])
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
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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.