Lucky for me, I already had an account, so here it is!
http://www.pinterest.com/toolazytodothis/biology/
Wednesday, April 30, 2014
Thursday, April 24, 2014
Wolves and Rabbits
In our
experiment, a pack of wolves was hunting four types of rabbits in an arctic
environment. The white rabbits had the
obvious advantage, since they blended in with the snow, but since what the
wolves ate was random (our paper throwing skills were not that great) the fact
that they were white was not necessarily advantageous. However, certain wolves had advantages in
this experiment, simply because they were bigger and could cover more rabbits
(and thereby eat them). This size
variation was essential to their success or failure, while the differences in
rabbits were less important. Every few
generations, a type of rabbit would go extinct, simply by bad luck or the
growing number of wolves. As the number
of wolves grew, the number of rabbits fell, until there were not enough to
sustain the wolves, which would then go extinct as well, and a new generation
of both rabbits and wolves would have to immigrate. The population of wolves would rise and fall
in accordance with the population of the rabbits, and when they both reached
their maximum, the wolves would begin to starve and die. This created a graph of almost sine-like
curves, which would intersect every couple generations.
| Generation | White | Yellow-Green | Teal | Green | Wolves |
| 1 | 1 | 1 | 1 | 1 | 1 |
| 2 | 2 | 2 | 2 | 0 | 1 |
| 3 | 4 | 2 | 4 | 0 | 1 |
| 4 | 8 | 4 | 6 | 0 | 1 |
| 5 | 12 | 6 | 10 | 0 | 2 |
| 6 | 20 | 12 | 10 | 0 | 4 |
| 7 | 20 | 14 | 16 | 0 | 8 |
| 8 | 8 | 8 | 10 | 0 | 16 |
| 9 | 4 | 0 | 0 | 0 | 6 |
| 10 | 0 | 0 | 0 | 0 | 0 |
| 11 | 1 | 1 | 1 | 1 | 1 |
| 12 | 2 | 2 | 2 | 0 | 1 |
| 13 | 4 | 4 | 0 | 0 | 1 |
| 14 | 2 | 8 | 0 | 0 | 2 |
| 15 | 1 | 10 | 0 | 0 | 2 |
| 16 | 0 | 18 | 0 | 0 | 1 |
| 17 | 0 | 30 | 0 | 0 | 2 |
| 18 | 0 | 46 | 0 | 0 | 4 |
| 19 | 0 | 50 | 0 | 0 | 9 |
| 20 | 0 | 22 | 0 | 0 | 16 |
| 21 | 0 | 0 | 0 | 0 | 6 |
| 22 | 1 | 1 | 1 | 1 | 6 |
| 23 | 0 | 0 | 0 | 0 | 0 |
| 24 | 1 | 1 | 1 | 1 | 1 |
| 25 | 2 | 2 | 2 | 0 | 1 |
 |
| Population of wolves and rabbits over 25 generations X axis: generation, Y axis: population number |
Monday, April 21, 2014
Meteor Impact?!
Every science fiction novel has come to life: there was a
meteor impact in the arctic!
Not only is this bad news for the meteor, but the fragile
ecosystem is in trouble too!
| http://www.telegraph.co.uk/science/space/8494145/Giant-asteroid-heading-close-to-Earth.html |
Abiotic:
When anything large falls to the earth, it releases mass
amounts of energy. This energy creates
huge gusts of wind that would knock over anything in the surrounding area. Of course, there aren’t that many tall trees
in the arctic, but this could potentially create a blizzard. In addition, this impact would create a huge
crater and destroy the surrounding layer of permafrost. The collision would kick up dirt and debris
in order to create what is called an impact winter. The dust in the air blocks the sunlight
(which wouldn’t have much effect in winter, but in summer could be disastrous)
and drives down the temperature. In
addition, this debris paired with the energy sends chemicals into the air,
which causes acid rain.
Impact winter:
 |
| Addison Wensley |
Biotic:
Everything in the path of the meteor would instantly be
vaporized in the explosion. What does
survive will have to deal with the aftermath, including but not limited to:
loss of shelter, scarcity of food sources, and declining temperatures. Since the arctic is already desert-like, it
would be close to impossible for animals to survive unscathed. Many would be unable to survive in the
colder, darker environment, and most would struggle to find food, as many
plants would be destroyed.
The animals in best shape would be those adapted to the coldest and darkest environments. Of course, arctic animals have a particular advantage, but that doesn’t make them immune. Animals able to turn to multiple sources of food and migratory animals would be the best suited to this disaster. For example, caribou can just leave and find more favorable environments in boreal forests. Predators like bears can eat almost anything (grizzly bears are omnivores so they would be best suited, while carnivores like polar bears would have a little harder time), so they could probably survive a shortage of food. On the other hand, herbivores would have to compete for a dwindling food source, since most plants would barely be able to survive.
 |
| http://www.sfu.ca/geog/geog351fall06/group03/Leah's%20Pages/Pages/Grizzly_Bear.htm |
| http://www.clg-pagnol-bonnieres.ac-versailles.fr/sciences/spip.php?article356 |
At a large scale, the minuscule number of organisms in the
arctic will fall even more. Many animals
would die of starvation, and plants wouldn’t receive enough sunlight or water
to survive. Overall, the whole ecosystem
would be ravaged, and it would take months, if not years, to return to a
semi-normal state.
Thanks to:
Thursday, April 17, 2014
Arctic Tundra Biome
 |
| http://www.telegraph.co.uk/earth/earthpicturegalleries/8283268/Pole-to-pole-Daniel-J-Cox-photographs-Arctic-polar-bears-and-penguins-in-Antarctica.html |
 |
| http://www.marietta.edu/~biol/biomes/tundra.htm |
Abiotic Features
Soil
type/minerals: The soil is lacking in nutrients, which barely matters since
hardly anything can grow in the tundra anyway.
Under the soil is a layer of permafrost, or a layer of ground that is
permanently frozen, all year long. Since
this layer is close to the top of the soil, there isn’t much room for plants to
take root.
Water: There is
little to no precipitation in the tundra, so it’s almost like a desert. Only about 6-10 inches of rain fall in the
tundra every year. This precipitation
can create small ponds, similar to the ones created when the weather gets
warmer and the frost on the ground melts.
 |
| http://climhy.lternet.edu/documents/climdes/arc/arcclim.htm |
Air: The
elevation of arctic tundra ranges from 300-10,000 meters, so the air pressure
varies depending on location, but is generally on the higher end of the
spectrum (low elevation means high pressure).
Since the tundra is basically a desert, it is not very humid, with
usually 5-10% humidity.
Temperature:
During the winter, the average temperature is about -30° Celsius,
with the lowest temperatures reaching -78°. During the summer, the average
temperature is between 3° and 12° Celsius.
So like, the tundra is cold right? We knew that, but we figured since it was summer we'd be okay. Yeah no. My dad loved the cold (about 50-60° F), but it was definitely not what I expected out of my summer. Us Californians are not adapted to that weather, and I was never as painfully aware of that as I was that week. (The cute husky picture may be a little unrelated, but I think it properly expresses the coldness, see his little sweater?!)
 |
| http://peanutpumpkinpie.blogspot.com/2013/01/peanut-economics-exploring-arctic.html |
Sunlight:
During the short summer, the sun is up almost 24 hours a day, giving the tundra
the name “land of the midnight sun.”
However, during the winter the sun only rises for several (if that)
hours a day, so it is almost always dark.
Prior to this trip, I was rarely up until even 11 PM. I maintain this is what made me a night owl, because it was literally only dark for like two hours a night, so I could NEVER sleep. Not that I really minded, since it was pretty interesting to see the "night" life.
Shelter:
There is not much shelter for animals, since the ground is relatively flat. There are some caves, but more animals use
snow caves for shelter during hibernation.
 |
| http://ed101.bu.edu/StudentDoc/Archives/ED101fa09/doamaral/Land.html |
Biotic
Components
Producers:
There are only 1700 species of plants in the arctic tundra, ranging from
flowering plants to shrubs. The growing
season is only about 90 days long, so these plants do not have much time to
take root. Some examples of tundra
plants are: arctic willows, bearberries, arctic poppies, and cotton grass. Like bearberries and pasque flowers, some
arctic plants are covered with fine, silky hairs. These hairs provide the leaves and stems with
insulation from the cold, which allows them to grow and continue photosynthesis
despite the freezing temperatures.
Apparently there is an equivalent of poison ivy in Alaska. I was not aware of that. You can assume what happened. The arctic flowers are really surprisingly pretty though, and the Native Americans had so many uses for them!
 |
| http://www.bbc.co.uk/nature/life/Papaver_radicatum |
Consumers:
There is not much biodiversity in the tundra, and many animals are migratory
and only reside there for the warmer parts of the year, such as birds and
caribou because of the relative lack of predators. Some tundra animals are: polar bears, arctic
foxes, snowy owls, and arctic hares. Of
course, these animals need some defense against the cold, so they have evolved
short ears to reduce heat loss, thick coats, and many hibernate during the
coldest winter months in order to conserve energy.
Bears! We saw bears! And birds of prey. And musk oxen, which smell...not as pleasant as you would expect them too. Also everything has this white fur that looks super soft and really pet-able...Look at this arctic fox! If that's not the cutest thing ever, you're wrong.
| http://www.zoo.org/view.image?Id=469 |
Decomposers:
The decomposers in the arctic work very slowly, because the cold slows down
their metabolism. In the summer,
mushrooms can grow, but for the rest of the year decomposition is almost at a
halt, so bodies of dead animals can still be around years after their death. Some decomposers are arctic moss, mushrooms,
and bacteria. Microorganisms like
bacteria have genes that allow them to survive in cold environments and can die
in warmer environments. These genes have
properties similar to antifreeze to give them the best capacity to survive, and
their genes have been useful in created human vaccines.
Yeah, that medication could have been useful. My dad got pneumonia (it started as a sinus infection, you know the curse: can't go on vacation without getting sick!).
Food Web
 |
| http://hwood6.wix.com/arctictundrabiome?_escaped_fragment_=arctic-tundra-food-web |
Symbiotic
Relationships
The most common
symbiotic relationship in the arctic is lichen, a combination of a fungus and
algae. The algae provide sugars to the
fungus, and the fungus protects the algae so it can survive.
 |
| http://www.aitc.sk.ca/saskschools/arctic/Aplants3.html |
Human Influence:
One very obvious
risk to the arctic tundra is global warming, a problem created by modern
society. Because the rising temperatures
have caused ice flows to melt, animals like polar bears often find themselves
displaced.
Another problem
created by modern society is a growing need for oil, much of which happens to
be found in the arctic. Drilling for oil
not only disrupts the environment, but leaves potential for pollution and takes
homes away from animals.
So, to plan my next trip to the arctic tundra, I guess I should reference this map!
 |
| http://www.marietta.edu/~biol/biomes/tundra.htm |
Thanks for going on this trip with me! Hope you have more biology-themed adventures of your own!
Sources/Sites to check out!
Want to help protect the arctic tundra?
Want to look at pictures of arctic animals just 'cuz? (I know I do)
Friday, April 11, 2014
Pill Bugs’ Response to Moisture, Scent, and pH (FOR STANDARDS)
Abstract
To determine which environments pill
bugs prefer, we performed up two different experiments to test conditions like
moisture, scent, and pH. We set up these
experiments in behavior chambers by laying filter paper on the bottom, and then
adding water, vinegar, and HCl. We then
added ten pill bugs to the chamber and recorded how many were on either side
after every thirty seconds, spending seven minutes on each of our three
trials. Our first trial, with a dry and
wet side, indicated that pill bugs prefer dry conditions. The next trial, with a water side and a
vinegar side, revealed that pill bugs prefer unscented environments. Our last trial, with a water side and an HCl
side, indicated that pill bugs prefer neutral conditions to acidic conditions.
Introduction
The dictionary defines behavior as “observable activity in a human or animal.” Basically, animal behavior is everything an
animal does, from eating to mating, and the mechanics behind these actions. The
science of animal behavior is called ethology, and it has several parts to it,
all starting with proximate and ultimate questions. Proximate questions have to do with the how
of a behavior and the mechanics behind it, while ultimate questions are about
the why of a behavior and what it accomplishes.
An example of an ultimate question is “Why does a bird sing?” or “Does
birdsong help birds mate?” An example of
a proximate question is, “What makes a bird know when to sing?” or “Is birdsong
a fixed action pattern?” Fixed action
patterns are behaviors that are ingrained in animals and happen in response to
a stimulus. Animals have never been
taught how to do these actions but rather know how to do them
instinctively. An example is bird-mating
dance, like when a male bird sees a lady bird he wants to woo. The stimulus, her presence, causes the male
to begin a dance like motion that must be carried to completion. Not all animal behaviors are unlearned
however, and imprinting is a big part of animal development. Imprinting is a period of swift learning in a
young animal’s life in which it very quickly attaches itself to a parent and
begins borrowing characteristics from it.
Young geese can imprint on humans or other animals, recognizing them as
a mother and following them around unceasingly.
A proximate cause might be that they are genetically compelled to find a
mother figure, and an ultimate cause could be that by finding a mother figure,
they are more likely to survive. The
tendency for geese to follow around their mother figure could be described as
taxis, or intentional movement. Taxis is
direct movement in response to a stimulus.
Kinesis is much less specific, and animals simply move around randomly
until they find suitable conditions.
This pill bug lab is an example of kinesis, as the pill bugs meandered
slowly until they found their preferred environment, where they stopped
moving. Stimuli are not only important
in movement, they are also important in other physical responses, as seen with
classical conditioning. Classical
conditioning is best known in Pavlov’s dogs.
He took a neutral stimulus, a bell ringing, and an unconditioned
stimulus, food, and made an association between them in the dogs’ minds. When the two stimuli became connected,
whenever the dogs heard a bell ring, they would begin to salivate like they
would if they saw food. Operant
conditioning, on the other hand, is more about voluntary actions and
incentive. By making an animal associate
an action with a reward, like giving a dog a treat every time he responds to a
command, the dog associates completing the command with something good, and will
voluntarily complete the action. So,
classical conditioning is more about involuntary responses, while operant
conditioning makes animals voluntarily act.
Hypothesis
Part
1:
If
pill bugs are given a choice between wet and dry environments, then they will
move toward the wet one because they normally live in moist conditions.
Part
2:
If
pill bugs are given a choice between environments with and without a strong
smell, then they will move to the scentless one because it is closer to the
conditions they normally live in.
If
pill bugs are given a choice between neutral and acidic environments, then they
will move toward the neutral one because it more closely resembles their
natural habitats.
Materials
Part
1:
-10
pill bugs
-2
plastic behavior chambers
-2
pieces of filter paper
-soft
brushes
-pipet
full of water
-timer
Part
2:
-10
pill bugs
-2
plastic behavior chambers
-2
pieces of filter paper
-soft
brushes
-3
pipets
-pH
strips
-water
-HCl
-vinegar
-timer
Procedure
Part
1:
First,
place the pill bugs in a behavior chamber, and observe them for a few
minutes. Set up the other chamber by
placing filter paper on the bottom of each side and dampening one side with
water. Use the brushes to carefully move
the pill bugs into the prepared chamber and place them in the center. Record how many pill bugs are in each
chamber, start a timer, and cover them with the other chamber, so it can be
dark like the pill bugs prefer. Every
thirty seconds, uncover the chamber and record how many pill bugs are on each side. Keep observing them for 7 minutes and then
graph the results.
Part
2:
Set
up the behavior chamber by placing filter paper on the bottom of each side and
dampening one with water. Take the pH of
a sample of vinegar and then dampen the other side of the chamber with it. Use the brushes to place the pill bugs in the
center of the chamber and record how many are on each side. Cover them with the other chamber and start
the timer. Uncover them every thirty
seconds and record how many are on each side.
Observe them for 7 minutes and graph the results. Set up another chamber by placing filter
paper on the bottom of each side and dampening one with water. Make an HCl solution by diluting the acid
with water until it has the same pH as the vinegar, and then dampen the other
side of the chamber with it. Place the
pill bugs in the center of the chamber, record how many are on each side, then
repeat the observation process for 7 minutes.
Graph the results.
Results
Part
1:
The
majority of pill bugs were always in the dry chamber, and most bugs did not
move at all. This indicates that the
pill bugs prefer dry environments as opposed to wet ones.
Time (min)
|
Wet
|
Dry
|
0
|
2
|
8
|
0.5
|
2
|
8
|
1
|
2
|
8
|
1.5
|
3
|
7
|
2
|
3
|
7
|
2.5
|
3
|
7
|
3
|
3
|
7
|
3.5
|
3
|
7
|
4
|
3
|
7
|
4.5
|
3
|
7
|
5
|
2
|
8
|
5.5
|
2
|
8
|
6
|
2
|
8
|
6.7
|
2
|
8
|
7
|
2
|
8
|
Part
2:
The
majority of pill bugs were always in the chamber with neutral pH, and again
most bugs did not move at all. The
experiment with the vinegar indicates the pill bugs prefer environments with no
scent as opposed to ones with strong smells, and that they might have a
preference for neutral environments, which was confirmed by the experiment with
HCl.
Time (min)
|
Water
|
Vinegar
|
0
|
4
|
6
|
0.5
|
6
|
4
|
1
|
9
|
1
|
1.5
|
9
|
1
|
2
|
9
|
1
|
2.5
|
9
|
1
|
3
|
9
|
1
|
3.5
|
9
|
1
|
4
|
9
|
1
|
4.5
|
9
|
1
|
5
|
9
|
1
|
5.5
|
9
|
1
|
6
|
9
|
1
|
6.7
|
9
|
1
|
7
|
9
|
1
|
Time (min)
|
Water
|
HCl
|
0
|
10
|
0
|
0.5
|
8
|
2
|
1
|
8
|
2
|
1.5
|
8
|
2
|
2
|
8
|
2
|
2.5
|
8
|
2
|
3
|
10
|
0
|
3.5
|
10
|
0
|
4
|
10
|
0
|
4.5
|
10
|
0
|
5
|
10
|
0
|
5.5
|
10
|
0
|
6
|
10
|
0
|
6.7
|
10
|
0
|
7
|
10
|
0
|
Conclusion
Our results indicate that pill bugs
prefer dry, scentless and neutral conditions.
While our hypotheses for part 2 were confirmed, our hypothesis for part
1 was proven wrong, much to our surprise.
We assumed that because pill bugs normally live in wet habitats that
they prefer wet conditions to dry ones, but that was not the case. Our control chamber, the dry one, seemed like
a more favorable environment in part 1, but in part 2 our constant, the water
chamber, seemed to be more appropriate for the pill bugs, who were another
variable we held constant. The chambers with
the extreme versions of the independent variables (pH and scent), containing
HCl and vinegar, were not popular among the pill bugs, leading them to choose
the wet chamber. This dependent variable
(number of pill bugs in each chamber) stayed relatively constant throughout the
experiment, but that may have been our fault.
We placed some of the filter paper wrong, and a few bugs got stuck
underneath it, so they were unable to move.
Some bugs we placed on their backs, so by the time they got oriented our
experiment was almost over. Overall, our
results make sense, even though part 1 was a little surprising for us. We managed to put our knowledge of animal
behavior to the test and design a working experiment to answer our questions
about pH and pill bugs, so this experiment was an overall success.
Questions
Part
1:
1. What conclusions do you draw from your
data? Explain physiological reasons for the behavior observed in this activity.
According
to our data, pill bugs prefer dry environments, although their gills would
indicate that they like wet environments.
This may be an adaptation to California’s dry climate.
2. How do isopods locate appropriate environments?
They
have eyes and sensitive antennae, which allow them to sense the brightness,
moisture, and other characteristics of their surroundings.
3. If you suddenly turn a rock over and
found isopods under it, what would you expect them to be doing? If you watch
the isopods for a few minutes, how would you expect to see their behavior
change?
When
our isopods made it to their ideal environment, they would stop moving, so I
would expect to see the isopods doing nothing.
After leaving them exposed to the sun and heat for a few minutes, they
would probably start moving around and looking for a more favorable
environment.
4.
Is the isopod’s response to moisture best
classified as kinesis or taxis? Explain your response.
Their
response was kinesis, since they moved randomly around until they found the
environment they preferred, and then stopped moving. They did not directly go to the dry chamber,
but instead meandered around, slowing down when they reached the ideal
conditions.
5. Identify the control(s), independent
variable, and dependent variable in this experiment and explain why you have
identified the factor you chose as each.
The
control was the dry chamber, because we did nothing to alter it.
The
independent variable was the moisture in each chamber, which was damp in one
and dry in the other.
The
dependent variable was the number of pill bugs in each chamber after every
thirty seconds, because this number was affected by the conditions set by our
independent variables.
Citations
Cherry,
Kendra. "Classical vs Operant Conditioning." About.com
Psychology. About.com, n.d. Web.
Meyer,
John R. "Elements of Behavior." Elements of Behavior. NC
State University, 2006. Web.
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