
Lecture 9
Insectivorous Plants
I.
Charles Darwin “Insectivorous Plants”
1875
II.
500 species of plants
A.
Nitrogen- poor soils
B.
Acid bogs
C.
Heavy volcanic clays
III.
Mechanisms to “trap” insects (attractant)
A.
Sticky exudates (attractive to insects) - fly
catcher, sundew

Insectivorous Plants
B.
Modified structures (color or nectar) -
pitcher plants
C.
Modified leaves (color or nectar-like
substance) - Venus fly trap
IV.
Digestion - glands secret enzymatic fluid to
digest insects (except exoskeleton)
V.
Absorb nutrients through plant tissues

Sundew
Pitcher plant
Venus fly trap - active trap
passive traps

What insects do for a living: phytophages
Phytophagous - feeds on living plants
(herbivores)
A.
Plants are primary producers (autotrophs)
B.
Insects are consumers (heterotrophs)
1.
Primary consumers - herbivory
(phytophages)
2.
Secondary or tertiary consumers (predators,
parasitoids, parasites)
3.
Scavengers
