Defense mechanisms
description
Transcript of Defense mechanisms
![Page 1: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/1.jpg)
Defense mechanisms• Camouflage– cryptic coloration
whipporwill
lizard
toadlizard
frog
![Page 2: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/2.jpg)
Mimicrypalatable or harmless species mimics a harmful model
Hawkmoth larva puffs up to look like poisonous snake
Batesian mimicry
hawkmoth larvae
green parrot snake
Convergent evolution
![Page 3: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/3.jpg)
Batesian mimicry
Monarch malepoisonous
Convergent evolution
fly bee moth bee
Which is the fly vs. the bee?Which is the moth vs. the bee?
Viceroy maleedible
![Page 4: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/4.jpg)
Mullerian mimicry
yellow jacket
cuckoo bee
two or more protected species look like each other
- group defense? - predators may evolve innate avoidanceMullerian mimicry
![Page 5: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/5.jpg)
Common warning coloration• Aposematic species come to resemble each other
black, red, orange & yellowmeans:DON’T EAT ME!
![Page 6: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/6.jpg)
What kind of mimicry?
Coral snake is poisonous
King snake is not
Red on yellow, poison fellow; red on black, safe from attack
![Page 7: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/7.jpg)
Coevolution in Community• Predator-prey relationships• Parasite-host relationships• Flowers & pollinators
Long term evolutionary adjustments between species
![Page 8: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/8.jpg)
Characterizing a community• Community structure– species diversity• how many different species
– composition• dominant species• most abundant species
or highest biomass (total weight)• keystone species• changes over time– succession
![Page 9: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/9.jpg)
Species diversitygreater diversity = greater stability
Greater biodiversity offers: more food
resources more habitats more resilience
in face of environmental change
![Page 10: Defense mechanisms](https://reader036.fdocuments.net/reader036/viewer/2022062305/56816595550346895dd8688b/html5/thumbnails/10.jpg)
suburban lawnagricultural“monoculture”
The impact of reduced biodiversity
“old field”
compare these communities
Irish potato famine 1970 US corn crop failure