Transcript PythonPowerPoint

The Python Problem
GRADE LEVEL: 6-8
TIME ALLOTMENT: Four 45-minute class periods
OVERVIEW: Using segments from the PBS series Nature episode, Invasion of the Giant
Pythons, students will explore pythons and their impact on other species. In the Introductory
Activity, students will learn about python digestion and unscramble photos illustrating a
python’s digestion of prey. In the Learning Activity, students will learn how pythons have
migrated to new environments and the dangers they pose to other species. Students will learn
how invasive species, such as pythons, can threaten native species. In the Culminating Activity,
students will learn about the Key Largo woodrat and ways scientists are trying to protect the
species from pythons. Students will then explore a native species in their own region and
create a presentation about the species, how it is being threatened, and efforts to protect it.
LEARNING OBJECTIVES:
Students will be able to:
■Explain where pythons live and how they have moved from
one environment to another.
■List python prey and discuss the process by which pythons
capture and digest food.
■Describe dangers pythons pose to native species.
■Discuss efforts to rescue the Key Largo woodrat and the
reasons why scientists are launching these efforts.
■Discuss one endangered or threatened local species and
efforts being taken to help that species.
Content Standard C: Life Science
Fundamental concepts and principles that underlie
this standard include:
The Interdependence of Organisms
• Organisms both cooperate and compete in ecosystems. The interrelationships and
interdependencies of these organisms may generate ecosystems that are stable for
hundreds or thousands of years.
• Living organisms have the capacity to produce populations of infinite size, but
environments and resources are finite. This fundamental tension has profound effects on
the interactions between organisms.
• Human beings live within the world’s ecosystems. Increasingly, humans modify ecosystems as a
result of population growth, technology, and consumption. Human destruction of habitats through
direct harvesting, pollution, atmospheric changes, and other factors is threatening current global
stability, and if not addressed, ecosystems will irreversibly affected.
MEDIA COMPONENTS
from netbook or device
Invasion of the Giant Pythons, selected segments
Clip 1: Dinner Time
An overview of how a python captures and digests its prey.
Clip 2: It’s Raining Pythons
A close look at how pythons have entered new environments
Clip 3: Beware: Pythons
A description of the dangers that pythons pose to other
species.
Clip 4: Saving the Rats
A look at efforts to protect the Key Largo woodrat from
pythons.
Websites
• US Fish and Wildlife Endangered Species Program
http://www.fws.gov/endangered/
• This website includes a variety of information
about endangered species. The “Species Search”
page (http://www.fws.gov/endangered/species/)
used in the Culminating Activity, features a US
map where visitors can locate endangered plant
and animal species throughout the country.
Websites Cont’
Optional (for research in Culminating Activity):
The Comprehensive Everglades Restoration Plan
http://www.evergladesplan.org/index.aspx
This website includes a variety of information
about the Everglades, including facts about
plants and animals:
http://www.evergladesplan.org/facts_info/sywt
kma_animals.aspx
Websites Cont’
California Department of Fish and Game/ Invasive Species
Program
http://www.dfg.ca.gov/invasives/. This website contains
information about invasive species in California and efforts
being taken to reduce their negative effects on native species
and environments.
South Florida Natural Resources Center/ Everglades National
Park: Natural Resources Management/ Burmese Pythons
http://www.nps.gov/ever/naturescience/upload/PythonFactS
heetHiRes.pdf. This fact sheet provides detailed information
about Burmese pythons and efforts underway to
monitor and control the python population.
Directions:
• Click audio to start.
What do you know about pythons?
Are they
venomous?
What rate do
pythons move
from one place
to another?
What prey
do pythons
eat?
Procedure on how to reply to blog:
1. Go to Mrs. LaRue’s blog
http://kangerooscience.blogspot.com/
2. Sign into Google with your user
name/password
3. Click on your hour and start your blog with
your last name and reply to questions on slide 8.
4. Complete this assignment by tomorrow,
Wednesday, 5-9-12.
Answer the following question before class
tomorrow:
Describe the
process by which
the python digests
its food.
Burmese Python
Python molurus bivittatus
Where do Burmese Pythons
live?
Native to the jungles and grassy marshes
of Southeast Asia, Burmese pythons are
among the largest snakes on Earth. They
are capable of reaching 23 feet (7 meters)
or more in length and weighing up to 200
pounds (90 kilograms) with a girth as big
as a telephone pole.
Where do Burmese
Pythons Live?
How do they kill their prey?
They kill by
constriction,
grasping a victim
with their sharp
teeth, coiling
their bodies
around the
animal, and
squeezing until it
suffocates. They
have stretchy
ligaments in
their jaws that
allow them to
swallow all their
food whole
Behavior of Burmese
Pythons
When young, they will spend much of
their time in the trees. However, as
they mature and their size and weight
make tree climbing unwieldy, they
transition to mainly ground-dwelling.
They are also excellent swimmers,
and can stay submerged for up to 30
minutes before surfacing for air.
Reproduction
Burmese pythons are solitary
animals and are generally only
seen together during spring
mating. Females lay clutches of
up to 100 eggs, which they
incubate for two to three
months. To keep their eggs
warm, they continually contract,
or shiver, their muscles.
What do we
eat?
Burmese pythons are
carnivores, surviving
primarily on small
mammals and birds. They
have poor eyesight, and
stalk prey using chemical
receptors in their tongues
and heat-sensors along
the jaws.
Key Largo Woodrat
(Neotoma floridana smalli)
Federal Status: Endangered
(August 31, 1984)
What is a Key Largo Woodrat?
The color of the Key Largo woodrat is described as sepia or
grey-brown above shading into cinnamon on the sides, with
cream or white ventral coloration. The forefeet are white to
the wrist and the hindfeet are primarily white to the ankles.
The Key Largo woodrat has large ears, protuberant eyes, and
a hairy tail. The head-and-body-length of the Key Largo
woodrat ranges from 120 to 230 mm, their tail length ranges
from 130 to 190 mm, and their hindfoot length ranges from
32 to 39 mm. Males, on average, weigh 258 g, while the
females tend to be much smaller, weighing only 210 g
Where they live
Habitat
The Key Largo woodrat is a resident of tropical hardwood hammocks,
the climax vegetation of upland areas in the Keys. Hammocks provide a
shady, humid microclimate with less wind and temperature variation
than more exposed habitats. The soils are poorly developed, typically
consisting of shallow humus and litter overlying the limestone substrate,
but may become deep in some forested areas.
Reproduction
The Key Largo woodrat is
capable of reproducing all year,
although seasonal peaks in
winter are evident (Hersh
1981). Key Largo woodrat litter
sizes range from one to four
young, with two most common.
Female woodrats can produce
two litters a year (Brown
1978b). Sex ratio favors 1.2 : 1
male to female (Hersh 1981).
Both sexes require about 5
months to reach sexual maturity
(Hersh 1981). The life
expectancy of the Key Largo
woodrat is unknown, but is
probably similar to other
subspecies of Neotoma
floridana, which may live for 3
years but probably average less
than 1 year (Fitch and Rainey
1956, Goertz 1970).
Guess what we Eat?
Key Largo woodrats are
nocturnal omnivores, but
feed primarily on a variety
of leaves, buds, seeds, and
fruits (Brown 1978b)
Bibliography
http://www.fws.gov/verobeach/MSRPPDFs/Key
LargoWoodrat.pdf
http://animals.nationalgeographic.com/animals
/reptiles/burmese-python