2. What in the world is a carnivorous
plant?
Must be able to attract,
capture and kill animals
(mostly insects)
Also must digest the animal
Can survive without eating
meat, though.
Most are small (<1 m tall)
but one vine species can
grow to be 10 m long
3. Where in the world can
I find these plants?
Everywhere except Antarctica!!
More abundant in Australia, southeast
Asia and North America
Even Alachua county has them!!
600 species and sub-species, but not
all related to each other
4. Where in the world can
I find these plants?
Hundreds of species of plants from
several genera are carnivorous.
Carnivorous plants are found all over
the world.
Their habitats range from grasslands to
swamps to under water, from
civilization to the jungles of the
Amazon.
5. Why aren’t all plants meat-eaters?
Carnivorous plants have an
advantage over non-
carnivorous plants in nutrient
poor habitats
In habitats with more nutrients,
non-carnivorous plants do
better because they do not
have to put energy into special
structures.
6. What animals do they eat?
Mostly Insects and spiders
(gnats, flies, moths, wasps,
spiders, butterflies, beetles and
ants)
Freshwater species eat small
water animals and fish and
mosquito larvae
Some capture small
amphibians (frogs) and small
birds and rodents have been
found in some tropical
species!!
Some species even eat insect
and bird excrement!!
7. How do these plants capture prey?
Can be sweet-smelling or
brightly colored to attract
prey to their trap
There are 2 types of traps
Active: Use rapid
movement (ex. Venus fly-
trap, Utricularia)
Passive: sticky hairs or a
long tube with hairs that
trap prey
9. How do they digest their prey?
Most produce
digestive enzymes
Some rely on bacteria
Some use both
bacteria and
digestive enzymes
10. What habitat do they live in?
The genus Utricularia is
aquatic (freshwater)
Mainly found in nutrient
poor wetlands (ex. Bogs)
Decaying plants release
acidic compounds
Microorganisms cannot
function
Difficult for plants to get
nutrients from acidic soil
11. How do we affect carnivorous plants
Only 3-5% of carnivorous
plant habitat left!
Draining wetlands
For roads, homes, stores
and water
Suppressing fire
Many ecosystems need fire
to stay healthy
Pollution from homes and
agriculture
Gets into water and destroys
plants
Poaching the plants: Many
are endangered.
12. Are The Plants Hard to Grow?
Carnivorous plants
can be easy to grow.
They can be
cultivated in a
greenhouse.
You can grow some
varieties in your
house as house
plants!
13. How do Carnivorous plants get their
energy?
They get their energy the same
way the other plants do...
Photosynthesis
14. Why do Carnivorous plants eat insects
and other small animals?
They eat insects and other small
animals because they live in places
where the soil is low in nutrients.
Carnivorous plants get the needed
nutrients from their “PREY”.
16. Catching the insect
The actual traps are located on the plants leaves
They attract their victims with a scent reminiscent of
food and a safe landing place
As soon as the insect settles, the leaf tips spring
instantly with lightning speed and within seconds the
insect is trapped inside the two halves of the leaf
There is a second where the plant tests what it has
caught using its sensory glands on the surface of its
lobes
If the prey contains protein, the trap clothes fully and
the digestion begins
17. The Digestion Process
Once the insect has been caught, it is
slowly dissolved by digestive fluids
produced by the plant
After many days, all that is left is the
insect’s exoskeleton, the hard outer
casing of the body
The rest has been absorbed by the plant
18. Vitamin Tablets
Carnivorous plants, like any other plant, also
use the process of photosynthesis to make
their own food
The insects they catch are only used as dietary
supplements
Like the equivalent of vitamin tablets for plants
Many plants need this extra source of food as
they grow in waterlogged ground where the
soil is lacking in nutrients and other essential
nutrients
20. Pitfall Traps(pitcher plant)
The pitcher plant is
basically a slippery leaf
wrapped into a tube
shape that contains a
pool of digestive
enzymes at the bottom.
21. Pitfall Trap (Cobra Lily)
Most Pitfall Traps have
the opening on the top
of the plant, the Cobra
Lily has an opening on
the bottom. When an
insect flies into it, it has
“windows” that let light
in but not insects out.
The insects are
attracted to the light
but cant get out.
23. Fly Paper traps(sundew)
Fly Paper traps are
coated with a sticky
substance called
“mucilage". When
an insect lands on
the plant it sticks to
it, after a while the
plant will curl
around it and digest
it.
24. Snap traps(Venus fly trap)
Venus Fly Trap has
small trigger hairs on
the inside, so if an
insect lands on it and
triggers only one hair
and flies off its lucky
but if it triggers more
than one it will cause
its own doom.
26. Let’s Review. . .
1) What are the 4 traits of a carnivorous plant?
They attract, capture, kill and digest animals
2) Do non-carnivorous plants share any of these traits?
Non-carnivorous plants can attract insects
3) Do they need to eat meat to survive?
No-they have been grown in labs without meat
4) Where in the world can you find these plants?
Everywhere except Antarctica
5) How many species are there? Are they all related?
600 species and sub-species; they are not all related
(convergent evolution)
27. Let’s Review. . .
1. What is the most common habitat of carnivorous plants?
Nutrient poor wetlands.
2. What feature of their habitat allowed them to evolve
carnivory?
The lack of nutrients available in the soil.
3. Why does the habitat have this feature?
pH of water is low, so bacteria cannot help decompose
plants and plants cannot take up nutrients as easily.
4. Why do non-carnivorous plants do better in habitats with
more nutrients?
Because they do not have to put energy into special
structures to capture prey like carnivorous plants do.
28. Let’s Review . . .
1. What do carnivorous plants commonly eat?
Insects, spiders and aquatic plants eat small animals, fish
and mosquito larvae.
2. Name 3 less common things they have been found to eat.
Amphibians, birds and rodents
3. What are the two types of traps they use to catch their
prey?
Active and passive
4. Name a variation of each type of trap.
Active: bladderwort (Utricularia), venus fly trap
(Dionaea). Passive: pitcher plant has a pitfall trap; most
carnivorous plants have sticky hairs.
29. Final Review and Wrap-Up
1) What are the 4 traits of a carnivorous plant? Do non-carnivorous
plants have any of these traits?
Attract, capture, kill and digest animals. Yes, many plants attract
insects for pollination.
2) How many species are there of carnivorous plants? Are they all
related?
600 species and sub-species that are not all related (convergent
evolution)
3) In what habitats and parts of the world are they found?
Found mostly in nutrient poor wetlands everywhere except
Antarctica.
4) What feature of their habitat allowed them to evolve carnivory?
Lack of nutrients
30. Final Review and Wrap-Up cont…
1) What are some of their common prey species? Some less common
ones?
Insects and spiders. Less common are amphibians, birds and rodents.
2) What are the two ways they capture their prey?
Active and passive traps.
3) How do they digest their prey (hint: what do some use to help them
digest?)?
Some secrete digestive enzymes, some use enzymes and bacteria to
help them digest (symbiosis).
4) How have humans affected carnivorous plant populations and their
habitat?
Humans have drained wetlands, suppressed fire, polluted water, used
too much water and poached plants.
31. Assignment
Draw your own carnivorous plant using only
plant parts.
Hinweis der Redaktion
These are carnivorous plants in the genus Cephalotus (Australian)
Many flowering plants have evolved ways to attract pollinators. Carnivorous plants just went one step further. . . Carnivorous plants have survived in laboratories without eating meat. The tropical genus Nepenthes has some vines that can grow 10 m long (picture is of a Nepenthes trap).
When species have evolved similar traits but are not related, it is called “convergent evolution”. Carnivory in plants is an example of convergent evolution.
When species have evolved similar traits but are not related, it is called “convergent evolution”. Carnivory in plants is an example of convergent evolution.
Carnivorous plants have adapted to the nutrient poor environments of some wetlands and have the ability to get their nutrients from meat-sources; thus, they have a competitive advantage over non-carnivorous plants ONLY IN NUTRIENT POOR HABITATS. In habitats with more nutrients, non-carnivorous plants do not have to put so much energy in specialized structures to capture prey, so they have a competitive advantage over carnivorous plants.
The first picture is a close up of a carnivorous plant leaf. The flies are stuck in the glandular hairs. The second picture is of the freshwater bladderwort plant ( Utricularia ) that captures small water animals in its bladders. Nepenthes is the tropical genus that small birds and rodents have been found in. However, this is not common at all and the birds and rodents must have been very sick to not be able to get out. Some plants have insects that live on them and kill the smaller insects that get trapped in the sticky hairs. These bigger insects excrete on the plant and the plants absorb it. But the weirdest of all has to be the plants that absorb bird excrement!!
The first picture is an example of an active trap. It is a Venus fly-trap ( Dionaea ), which has a trap that closes shut quickly when the trigger hairs are touched. The cells on the inside of the trap become limp and the leaf closes. The second picture is a passive trap (sticky, glandular hairs) of a sundew ( Drosera ).
Top left: A close-up of an african Drosophyllum (sundew) . It has sticky, glandular hairs that insects get trapped in and the plants slowly digests them. When the insect gets trapped, the tentacles bend towards the prey due to irregular cell growth. Top right: Pinguicula reticulata , a small plant with sticky, glandular hairs. Bottom left: Sarracenia alabamensis , a species found in Alabama, has a pitfall trap. The reddish color on the plant attract insects to the trap. They walk in and fall down the trap, which has waxy walls and hairs pointing downwards, and they can’t get out. They drown in the digestive juices at the bottom of the trap. Bottom right: Utricularia (the freshwater carnivorous plant) has an active trapping system, made up of small bladder-like structures (common name is bladderwort) that it can suck prey into in about 1/30 of a second. **Next show the videoclip from the internet of the venus fly-trap ( Dionaea ) capturing prey and the short animation clips of Drosera, Utricularia and Drosophyllum.
The picture is the partially digested contents of insects in a carnivorous plant. They produce very mild digestive enzymes that slowly digest the animals that they capture. Bacteria often live on the carnivorous plant and they secrete their own digestive enzymes (the plant sometimes also has its own enzymes). This is an example of symbiosis, because both the bacteria and plant benefit (bacteria gets food and a place to live and the plant gets help digesting).
The decaying plants release acidic compounds, which accumulate in the water. There is no outflow of water, so these acidic compounds stay in the water and make it acidic (lower the pH). Two things happen when the pH of the water is lowered: 1) Microorganisms that aid in decomposition cannot function, so dead plants do not decay (they just sit there). With such low decomposition, there are few nutrients available. 2) When soil is acidic, it is difficult for plants to assimilate nutrients, so the few nutrients that are there, the plants cannot take up. The first photo is of a Sarracenia (pitcher plant) bog, the second is of a rocky mountain wetland.
Only 3-5% of carnivorous plant habitat remains! Many habitats, especially in Florida, need periodic fires to keep out species that don’t belong and regenerate species that do belong. Water pollution can kill carnivorous plants. When we take too much groundwater (for drinking, industrial and agricultural uses) this can lower the water table, which can take the water out of wetlands and kill the plants that need water to survive. Carnivorous plants are very beautiful and intriguing plants, so people often collect them from the wild. This hurts wild populations and has even put some species on the endangered species list. All Sarracenia , Nepenthes and Dionaea muscipula (the venus fly trap) are on the endangered or threatened species list. This means that it is illegal to kill (or take) any part of these plants. You can be fined $1000’s of dollars for harming them or taking them. If you are interested in owning some carnivorous plants, there are many nurseries that sell plants that were not poached from the wild. The picture is of a drained wetland in Florida.
Answers: 1) They can attract, capture, kill and digest animals (insects) 2) Non-carnivorous plants can attract insects (for pollination) 3) No-they have been grown in labs and survived with no meat. 4) Everywhere except Antarctica (most abundant in Australia, SE Asia, and North America). 5) 600 species and sub-species: No, they are not all related, they all separately evolved the trait of carnivory (convergent evolution).
Nutrient poor wetlands The lack of nutrients available in the soil The decaying plants release acidic compounds, which accumulate in the water. There is no outflow of water, so these acidic compounds stay in the water and make it acidic (lower the pH). Two things happen when the pH of the water is lowered: 1) Microorganisms that aid in decomposition cannot function, so dead plants do not decay (they just sit there). With such low decomposition, there are few nutrients available. 2) When soil is acidic, it is difficult for plants to assimilate nutrients, so the few nutrients that are there, the plants cannot take up. 4) Because they do not have to put energy into specialized structures like carnivorous plants do.
Insects, spiders and the aquatic plants eat small animals, fish and mosquito larvae. Amphibians (frogs), birds and rodents Active and passive Active: Utricularia (the bladderwort) has small bladders that suck prey in. The venus fly trap ( Dionaea ) has a trap that closes very quickly when an insect touches the trigger hairs. The cells on the inside of the trap become limp and the leaf closes. Passive: The pitcher plant has a pitfall trap that insects crawl in and can’t get out because of the waxy coating and hairs pointing downwards. Many carnivorous plants have glandular hairs that insects get stuck in and then the plant digests them.
They can attract, capture, kill and digest animals (insects). Non-carnivorous plants attract insects for pollination. 600 species and sub-species that are not all related (convergent evolution). Found most commonly in nutrient poor wetlands everywhere except Antarctica. Lack of nutrients.
Insects and spiders. Less common are amphibians, birds and rodents. Some capture prey for insects to eat and eat the insect feces, some eat bird feces. Active and passive traps. Some secrete digestive enzymes, some use enzymes and bacteria to help them digest (symbiosis). Humans have drained wetlands (destroyed habitat), suppressed fire (detrimental to many carnivorous plant habitats around the world), polluted the water (kills the plants), used too much water which lowered the water table, and poached plants (many species on endangered species list).