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Bio 103, Lab 1, Darwin's Voyage Revisited

Paul Grobstein's picture

Life has recently been discovered on two planets, currently named Nearer and Farther. Survey expeditions are being undertaken to characterize life on each, with the objective of comparing the charcteristics of life on the two planets both with each other and with life on earth. The general effort is to better understand general properties of living systems.

Expeditionary groups have been formed to undertake an initial survey of "plant" life on Nearer and Farther. Plant life on earth is characterized by substantial diversity; there are a large number of different kinds of plants. The goal of the expeditionary groups is to try and determine whether diversity of plant life is an idiosyncracy of life on earth or a more general property of life wherever it is found.

You are a member of one such expeditionary group. Your group must return with a scheme for categorizing plant life on the planet assigned that is well motivated by your observations, clearly described, and yields a definite quantitative result for the numbers of kinds of plants on that planet. You will of course need to use understandings of the meaning of "plant" derived from experiences on earth, but you should not presume that categories of plant life on Nearer and Farther are necessarily similar to those on Earth. Your report should note presumptions about what plants are, be clear about what observations motivate your categorizing scheme, provide some indication of the level of confidence you have in your quantitative results, and discuss what further observations are motivated by your findings . A preliminary report of your studies will be presented at a conference on "Diversity in BioSystems: New Findings From Additional Cases", focused on the question of whether "diversity" is or is not a fundamental characteristic of living systems.

Your group should also publish a summary of its findings in this forum. Be sure to include in the text of your summary the names of all team members.

Some related readings:

ktan's picture

Paoli, Laura, & Kristel

Short summary description of objects observed:
∞ (airconditioner): smooth, moves on its own, reacts to outside force, highly organized, has texture
∆ (trees): reacts to outside force, tall, cylindrical, green and brown, creates sound, pointy, rough texture, organized
Ο (rock): no movement, hard texture, homogenous, fairly organized, big, does not react to outside force
* (buil (stump): short, a part of the ground, old, malleable, weak
X (spider): moves on its own, dark, small, organized, reacts to outside force
Ω (shrubs/bush): reacts to outside force, extensions, big, thin, long
Next, we defined (based on our own definitions) five categories which we thought would help categorize the objects we observed. We used "size," (measured in comparison to us) "texture," (soft or hard to our touch) "shade," (based on greyscale-dark=brown/grey) "organization," (if the object shows some form of pattern or has multiple parts) "movement" (whether it responses to our force).
Ω : responsive, complex, light, soft, big
X : responsive, complex, dark, soft, small
π : responsive, simple, dark, soft, small
= : non-responsive, complex, light, soft, big
* : non-responsive, simple, light, hard, big
Ο: non-responsive, simple, dark, hard, big
∆: responsive, complex, dark, hard, big
∞: non-responsive, complex, dark, hard, bigding): organized, spaced evenly (seems to be artificial), large, hard texture, no reaction to outside force,
= (ground): flat surface, somewhat lumpy, soft, doesn't react to outside force, has a variety of objects on it
π (stump): short, a part of the ground, old, malleable, weak
X (spider): moves on its own, dark, small, organized, reacts to outside force
Ω (shrubs/bush): reacts to outside force, extensions, big, thin, long
Next, we defined (based on our own definitions) five categories which we thought would help categorize the objects we observed. We used "size," (measured in comparison to us) "texture," (soft or hard to our touch) "shade," (based on greyscale-dark=brown/grey) "organization," (if the object shows some form of pattern or has multiple parts) "movement" (whether it responses to our force).
Ω : responsive, complex, light, soft, big
X : responsive, complex, dark, soft, small
π : responsive, simple, dark, soft, small
= : non-responsive, complex, light, soft, big
* : non-responsive, simple, light, hard, big
Ο: non-responsive, simple, dark, hard, big
∆: responsive, complex, dark, hard, big
∞: non-responsive, complex, dark, hard, big
In conclusion, we found that only one object belonged to a set of categories. We encountered several problems as we were categorizing the objects we observed, which mainly involved the fact that we had to use human societal assumptions.
sophie b.'s picture

Chronicles of Planet Farther Away!

We arrived on Planet Farther Away in the midst of a fierce windstorm.  Captain Sophie stepped out onto what first appeared as a massive stretch of seemingly lifeless green and brown land.  Our senses were bombarded with the overpowering presence of vibrant green, in various shapes, shades, and sizes. 


We approached the brown monolithic structure in the center of the planet.  Upon close observation of both the monolith and the ground, we saw that the green in every case was emerging from brown.  The main point of confusion to our team was that there were flat structures of identical size and shape that were different colors, based on location.  The ones on the ground were brown and appeared in various stages of erosion, while the ones on the monolith were green and whole.  We decided that the two must be varying states of the same structure, and one must be alive, the other dead.  We observed the monolith in closer detail to see what the difference might be.  While probing the monolith with her lightsaber, Captain Sophie was attacked by a small flying specimin that flew towards her face in defense.  Such a clear sign of life indicated that the Monolith was a source of life in many varieties! 


Given that the green grew from the monolith, it became clear that green indicated life, while brown was the source of energy for life.  Returning to observe the surface level, we saw that all green structures on the ground also emerged from brown!  Eureka!


We began to search for diversity in the life forms.  A hierarchy emerged in the alien life.  The formless and flat green attached to the monolith was the least complex form of life observed (hereafter referred to as Specimen A).  In various stages of decomposition Specimen A would become flaky, perforated, and moved along the color spectrum from green to brown.  The flat needlelike blades of green that overwhelmed us upon first glance was disappointingly low down on the hierarchy. (Specimen B) While prolific, Specimen B is of a minimal level of complexity, with just one line dividing it in half.  What initially appeared to be a variety of Specimen B we realized was in fact another species entirely.  It is the same height as Specimen B, but is divided into three separate modules, each of which is then divided in half, like a fractal.  (Specimen C)  These consisted of the base life forms on the ground.

The next organisms, which were clearly a higher level of structure, consisted of life forms that were green and flat, like the previously classified specimens, but were highly subdivided on an internal level (as opposed to the external subdivisions of Specimen C.)  These were emerging from the monolith, as well as pseudo-monoliths on the west side of the planet.  We devided these into two separate organisms based on the complexity level of the internal structures (as seen by the lines/veins running through them.)

Specimen D were the structures on the monolith, hanging precariously off the tapering ends of the brown monolith, swaying surreptitiously in the windstorm. They had five main lines and many veins running through them. Specimen E, a variation of Specimen D, was slightly more complex. We concluded that the reason behind this was the increasing ratio of the brown source of energy for life to green. 

-- As observed by Jesse Ingber, Yashaswini Singh, Sophie Balis-Harris!

cejensen's picture

"Life" on Planet Farther

  Back from our adventures in space we came across this foreign planetary organism. When we arrived on Planet Farther, we were immediately struck by the amount of green we observed in the landscape. We saw many green structures, some larger brown structures with green appendages, and some soft green ground covering. We began our investigation in an area where the smaller green structures were heavily concentrated. There were a lot of them, many of them had all of the same characteristics and some were slightly different from each other. The smaller ones were lighter in color, and the larger ones were darker. Each individual had many different appendages of different sizes and sometimes different colors. In instances mentioned above when some of these structures were slightly different from one another, it was the shape of these appendages that differed. We developed a couple of ideas about life on this planet based on these findings. One idea that became the basis for the rest of our investigation is that we believe that on this planet green = life. We think this because we believed that we saw evidence of growth in these specimen, and we also saw what we believed to be dead specimen, as they were dry, not green (orange, brown, yellow, and red), and not connected to anything. The smaller ones were a lighter green and the larger a darker green, we believe that the lighter color of green indicated a younger specimen because it was smaller. Another thought we had about a requirement for life on this planet was being connected to the ground, because all of the specimens that we found that were green and showed evidence of growth were also connected to the ground. Even the larger brown structures were connected to the ground and were tinted green on the outside. There were smaller versions of these as well, that seemed to grow out of the larger structures. They were thinner and smaller overall, and also a lighter color and more green. We thought that these were "baby" versions of the larger structures, this being evidence of reproduction and therefore, we said, life. When we looked at the "ground covering" again, we decided that according to our criteria it too was life.

Taking all of this into account, we developed three different theories, a) that all of these organisms are seperate individuals, b) that the entire "planet" is in fact one single living organism, and c) a combination of a and b, that there are many smaller organisms growing on one larger organism (that some of the structures are part of one individual while others are separate organisms). Our basis for theory b was that all of the green things are connected to the "ground," and that they might perhaps all just be different parts of one organism. We didn't come to a conclusion about which theory is more plausible, but we are leaning towards theory c.

By Claire Jensen and Keshia Koech

xhan's picture

Michelle, Valerie, and Emily's Magnificent Adventure

When we landed on our planet, we looked around from where we stood, and decided to sit down and look first at what was below our feet.

The first (and most abundant) characteristic of this land was the color green, especially on the ground. Upon closer inspection of the ground, we noticed that the green color we saw took several physical forms and some different shades of green.
The first object we observed had wiry, green protrusions from the ground. It was attached to the ground in a spreading, vein-like pattern. Its length stood anywhere between the length of an average human pinky to an average human middle finger. At the top of the wirey part, there were three flat, tear-dropped shapes, each with a middle crease,each about the size of a finger nail.
Thing 2: this thing was also green and attached to the ground. We found many other specimens on this planet that involved the color green and were ground-bound, so we made an abbreviation/acronym for this type of thing: "gg" for "green" and "ground". The second thing was hair-like, protruding from the same origin, in a bunch. A few strands tend to share a bottom pinky nail length tube structure. It was dispersed throughout but less abundant than object one.
Thing 3: This object was not attached to the ground-- free moving. It was slippery/sticky and cold feeling. Beige colored length of a thumbnail. There was a repeating oval pattern on the surface with two points (dark brown) protruding from one end. As it moves, it leaves a shiny trail. Three were observed together. Protrusions went back to its main form-- seems like a defense mechanism.Because this object was free moving (unattached to the ground) and because we saw future objects that were free moving, we made an acronym for similar objects labeled as FM.
Thing 4: GG This object is a yellowish-green color. It is fuzzy in texture and is attached to the ground. It is easily pulled from the ground. When pulled up from the ground, it looks the same as the part above ground, but it was brown and carried dirt with it.
Thing 5: FM This object is shiny, is reddish brown in color and fast-moving. It is small-length of pinky nail, and has 8 tiny attachments protruding from body. It has 3 spheres of main body(protrusion is attached).
Thing 6: F… This thing was not attached to the ground, but it did not move on its own. It was flat, and dark-red, with hint of orange and yellow, creating some pinkish tint as well. Shape was a symmetrical, 5 point star, with two adjacent points spread away from each other to create 180 degree line. There was a line coming from each of the 5 points, all meeting at/coming from a single point at the midsection of the previously described two-spreading points of the star. At this point, there is a protrusion from the flat star-plane at this point that sticks out.
Thing 7: FM This object was green and had six moving protrusions like thing 5. There was an orange line running down its back in the middle and it was in a teardrop shape. There were two reddish, very small protrusions coming from the top of the front. There were three kinks in each lower protrusion (leg-like structures) with orange/brown tips.
Thing 8: GG Bigger than other GGs that we observed previously. Shiny, flat ovals attached to either side of a brown protrusion. The first protrusion comes from the ground and then splits into other protrusions. The shiny side of the ovals is facing up to sky. There is a vein-like structure that starts from the ground and splits into others.
Thing 9: GG Largest GG we observed, about the height of one and a half humans. Lots of brown protrusions starting from one central attachment to ground. The green parts are very pliable whereas the brown parts are rough and stiff. The green parts are flat, nail-length, thin symmetrically opposing. The tips are light green. There were red spheres, diameter of a pinky nail thinly scattered. The red spheres were also slightly transparent. There is a whole in the bottom of each sphere with a green circular object in it.


drichard's picture

Upon return from our

Upon return from our harrowing journey to the distant and recently charted planet Nearer, we cataloged our highly varied samples and recorded our observations. Our discoveries are listed below:

Employing our knowledge of earthly plant-life, we made observations about the growths covering planet Nearer. We looked at the texture, colour, size, and general position. We found that many of the growths resembled the plants we know here on earth. In the following list quotations mark temporary names for the growths based on their convenient similarities to earth-dwelling plants.

We observed three "trees," two "shrubs," three forms of "moss," "clovers," and several types of grass-like "weeds."

"Trees" All trees were rooted in the floor of planet Nearer. It appears that plant life unconnected to soil of some sort will eventually perish on planet Nearer, pointing to the need for soil-based resources. All trees had leaves. It can be implied that Nearer's trees also need water-like fluids (the function of leaves is to catch fluids). All trees appear to be deciduous growths, changing composition and colour based on a shift in environment (i.e. seasons). Leaves that fell from the trees met their demise on Nearer's floor. All trees exhibited a certain tropism; the branches of each seemed to grow in a similar direction towards the light source over planet Nearer. This points to the need of light.

"Moss" We observed three forms of moss that grew along the floor of planet Nearer: some growing on the trees, mainly towards the bottom of the trees, closer to the soil; some along the floor meshing with the grass but closer to the bottom of the trees. Utilizing our knowledge of substances on Earth and applying it to the observations that we made on planet Nearer, and taking into account the notion of "location" through our observations, we concluded that the moss that grew on and near the trees had access to a source of "water." Mosses on Earth are found in areas of dampness and low light and when applying our knowledge of the moss on Earth for planet Nearer, we made the implication that the moss on planet Nearer must be similar, which makes sense based on our observation of the moss that grows along the bottom of the trees and on the floor near the bottom of the tree. The location of the moss on planet Nearer is one that is away from sunlight. And since water is absorbed into the ground, the "soil", the moss seems to behave like the moss that is found on planet Earth.

"Shrubs" During our stay on the planet we observed two different types of shurbs.  We gave them names that reflected the physical nature of their leaves.  One shrub had needle-like leaves and was therefore called the 'porcupine shrub"; the second shrub had thin leaves which reminded us of fingerprints.  This second shurb was named the 'pinky shurb'.  Using the shurbs as tools of observations, we were able to observe that there were less plants under both shurbs, but there were a large amount of plants around the shurbs.  From this we were able to observe the importance of sunlight to these plants.  Without sunlight, plants will not be able to grow and survive.  

Terrible2s's picture

Planet Farther: Foursome

On Planet Farther we have discovered many different forms of non- human photosynthesizing entities. Of these entities we have separated them into 2 major categories: dependent and independent. We define dependent as bodies that grow directly on the surface of the base of another entity. We have found only one instance of this body, herein after named Parasitic Growth #1.

We define independent entities as bodies which protrude directly from the ground. All bodies which we deem to be independent fall into one of the two following categories:  1)Smooth, Flexible, Single-Colored Ground Growth (SFSCGG) and 2) Multi-Layered Base with Limbs and (sometimes) Sub-Limbs (MLB).  Of the SFSCGG, there are three subcategories: 1) Single-Pronged with (sometimes) Sub-Limbs, 2) Multi-Pronged. Of the MLB, we observed two distinct categories: 1) growths with Single-pronged Bases, and those with 2)multi-pronged bases.

We had difficulties differentiating the types of plants and keeping track of the terminology we used to categorize them. We also had difficulty eliminating our Earthly perspective. In the future, we could spend more time on Planet Farther in order to accurately observe the plant life and portray representative findings.


JPierre, Terrible2s, Dchin, Anna Chiles

heatherl18's picture

Farther Plant Observations

Karina Granadeno, Mariah Casias, Heather Lewis

We discovered eighteen different types of plants on the planet Farther, and classified them into six categories. When classifying plants, we took particular note of two factors in particular. One factor we took into consideration was plant height. We classified them into tall, medium, and short. The other factor we took into account was whether the branches grew from a central trunk, directly from the ground, or neither. One difficulty we encountered was how each category was defined. Even if we had been able to measure the height of the plants quantitatively, the classifications “tall,” “medium,” and “short” are fairly arbitrary. There is no set number that makes something “tall,” so inevitably, some plant heights were ambiguous, and were assigned differently by each of us according to no standard but opinion. Another difficulty was making classifications that fit every plant. Each plant has specific characteristics, making it hard to make general categories that apply to each plant. What we can take away from this is that categories in general are fairly arbitrary and subject to the opinion of the people who define them. Even within each category, there is a lot of variation, and we would have to make an infinite number of categories to attempt to encompass them all.


JJ's picture


What is a plant under our standards?
                It is everything attached to the ground; part of the plant’s anchor goes under the ground; it has no heartbeats and it must have an external force to move it.
How did we classify the plants?
                Distance from top of plant to soil:
                Closest to ground (under 1’)
·         Concrete
·         Small green leafy bodies
Medium (1’-10’)
·         Benches
·         Poles
·         Stump
·         Rail
·         Bush
·         Pipes
·         Stairs
Tall (above 10’)
·         Lamppost
·         Building
·         Pipe
·         Large green leafy bodies
Strength of Anchor- Can humans move plant with their hands?
·         Small green leafy bodies
·         All other observed plants
Other observed objects that were not classified as plants:
·         Humans
·         Vehicles
·         Sticks
·         Potted green leafy objects
Problems with making new observations:
                We had problems with differentiating between plants and objects that appeared similar to those attached to the ground. We were also limited by not having standard tools or a system of measurement to measure size or strength of the plants’ anchor. We initially talked about whether objects (potential plants) were growing or not, but decided that we had not been on Planet Nearer long enough to observe that.  
                What we would do on a next visit:
                We would stay for longer in order to observe the potential growth of plants that we’ve already identified. We would create more classification groups and sub-groups in order to differentiate between the many species (i.e. there were multiple species of concrete). We would create a standard system of measurements.  We would determine what the function was of the plant.

 Lili Elsesser, Maria Miranda, Juliana Jacquemin