Symbiosis

1
Symbiosis

• 2 species with a long-term close association
• One organism ALWAYS benefits

2
Three types of symbiosis

• MUTUALISM
• Mutually good
• BOTH organisms benefit! Everybody wins!
• Examples
• Bacteria in your intestines. They get food from
  you so they benefit. They make Vitamin D for you
  so YOU benefit too!
• Algae living in coral. Algae get shelter from
  the coral so they benefit. The coral gets extra
  food that the algae makes, so the coral benefits
  too!

3
Commensalism

• One organism benefits, the other is not affected
  either way. It isnt harmed or helped.
• Examples
• The small remora fish swims next to a shark. It
  feeds off scraps of food left by sharks. The
  shark isnt helped or harmed by this. He doesnt
  care!

4
Parasitism

• One organism benefits (the parasite), but one
  organism is HARMED (the host).
• Examples
• The dog tick feeds on the blood of a dog. The
  tick benefits, but this weakens the dog. The dog
  is HARMED.
• The tomato hornworm ( a caterpillar) is HARMED
  when wasps lay eggs on the caterpillar. When the
  eggs hatch, the young wasp will eat the
  caterpillar. The caterpillar will die.