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Bio 103, Lab 2, Darwin's Voyage Revisited Revisited

Paul Grobstein's picture

The funding agencies were impressed by the results of the initial surveys of plant life on Nearer and Farther. The findings clearly indicate that there is a diversity of plant life on both planets, while highlighting difficulties in categorizing such life (problems that are familiar from previous experience on Earth). In general, more effective categorizing schemes seem to involve

  • acknowledgement of the possibility that the appearance of individual organisms may change over time
  • descriptions in terms that can be conveyed as unequivocably as possible to other observers, including quantification where possible
  • the use, where possible, of qualitative (logically exclusive) instead of quantitative characteristics
  • the observations of "natural clusters" in which
    • there is an absence of intermediate forms
    • several different characteristics correlate with one another

The funding agencies also suspect that additional observations at other than normal human scales might help to further characterize the diversity of plant life on Nearer and Farther .

With the objective of getting less wrong about characterizing plant life on Nearer and Farther, each of the original expeditionary groups is encouraged to make a second expedition to the planet they did not visit on their first expedition. Each group should prepare for that expedition by reading a prior report on that planet.   The new expedition should focus on plants that are less than 1 meter and include both naked eye observations and observations at the scale of centimeters and millimeters. Additional equipment will be provided to facilitate this shift of scale.

The report of each group should include a summary of  observations of patterns of similarities and differences among plants at the two observational scales, a critical evaluation of the prior work on that planet with regard to numbers of kinds of plants, and a discussion of whether plant life appears more or less diverse when viewed at successively smaller spatial scales.

Relevant information about plant life on earth:

In the event of inclement planetary conditions:

Your group should create a classifying scheme for a selected group of earth organisms (pictures provided).  After doing so, you should compare your classifying scheme with ones used by professional biologists, as exemplified by one of the two following

Your group's report should describe the rationale and logic of the classifying scheme you develop and discuss its pros and cons relative to that of whichever other classifying scheme you working with.  See classification: uses and caveats

For what purpose is one classifying?

Is there "nested clumpy diversity"?


xhan's picture

Smooth vs Rough

We (Yashaswini and Michelle) categorized different organisms based on the complexity of their textures. The outer-boundaries of most of them varied from smooth, flat, one-dimensional to rough, furry, and three-dimensional textures.

A.      Smooth Organisms
1.       Flimsy and Irregular shaped
·         Bacteria: pseudomonas aeruginosa
·         Streptococcus
·         Amoeba
·         Euglena oxyuris
·         Flatworm Stylochus
·         Volvox
·         Jellyfish
2.       Relatively Flat(Green)
·         Barley Grass
·         Firn
·         Seaweed
3.       Terrestrial Smooth 
·         Mushroom
·         Leech
·         Small Garden Slub
·         Flatworm
·         Earthworm
4.       Marine Smooth
·         Brown Trout
·         Channel Catfish
·         Eel
·         Killer Whale
B.      Rough Organisms
1.       Furry/Hairy
·         Wild Dogs           
·         Kangaroo
·         Squirrel Monkey
·         Gorilla
·         Lion
·         Penguins
·         Human
2.       Leafy/With Bark
·         Redwood
·         Blue Oak
·         Rock Rose
3.       Scaly and Shelled
·         Lobster
·         Cockroach
·         Spider
·         Ischonodermus Sabulet
·         Turtle
4.       Wings/With Feathers
·         Owls
·         Butterfly
·         Fly
·         Eagle
·         American Robin
·         Ostrich
5.       Miscellaneous outward protrusions
·         E Coli
·         Sponge
·         Sea Urchin
·         Coral
·         Octopus
However, on comparing our ingenious (!) classification style with that of professional biologists, we discovered quite a few discrepancies. For example, professional biologists have categorized E Coli under bacteria and Sea Urchins under Chromista; while we categorized these organisms under organisms with miscellaneous outward protrusions, as the projections on both had an uncanny similarity to each other (pink and needle-like), though the projections on the sea-urchin are infinitely bigger than those on the EColi. Another discrepancy was that of the butterfly and the owl. While we categorized them together as organisms with wings and feathers, professional biologists have classified them under Aves (the owl) and Insecta (the butterfly).




ktan's picture

Upon further investigation...

We, Claire, Kristell, Laura, and Emily traveled to planet farther to compare what we observed aw to what the astronauts before us observed. Our macro-observations generally matched those of the previous explorers, but upon closer observation (with a magnifying tool), we found more forms of life (so we suspect). We spotted a rather large, mostly brown object which matched a description the previous group had. The previous group had claimed that when they "attacked" it, it had something fly at them-- i.e. it defended itself. When Emily did the same, at first there was no reaction from the "organism". Upon shaking the organism more vigorously, however, about five things flew at/fell on her from above, but did not harm her. We do not know whether this was a voluntary action or a physical reaction (involuntary) due to the force Emily applied.

Smaller observations:

We observed what we thought was a family of organisms that were mostly similar but had some variation in the shapes of their appendages (see figure A). Upon a closer look, we observed that each organism shared the following similarities: they were all green, and they all had the same general structure (a tall, upright, thin protrusion from the ground and one or many appendage(s) at the top). Where there was variance in height or appendage size, we concluded that the difference(s) did not necessarily indicate different breeds-- the smaller versions tended to be lighter green, and attached to the larger versions of the same appendage shape. That made us believe that the smaller, lighter versions were the younger, newer regenerations of the larger organism(s). When we used a magnifiying glass we observed that there were similar patterns on every one of the different appendage shapes, looking roughly like human skin does (a hand, for eg) under a magnifying glass. It had a triangular pattern with "pores." We believe that the different appendage shapes indicates the different breeds of the same species.


Similarities in our catagorization/classification scheme in comparison to the two previous explorers' schemes:


-bound to ground

-evidence of growth


Differences/additions in our catagorization/classification scheme in comparison to the two previous explorers' schemes:

-free moving, individual organisms

-Close-up patterns in appendages (leaves)

-White as a new color signifying life (and ground-bound)

Most of these observations were made with the aid of the magnifying glass. There were more patterns (or lack thereof) between similar things (organisms?) that lent themselves to further, detailed comparison and contrast between species or breeds.


-that closer inspection of detail lets us get closer to figuring out whether things are related or not.

-all the green, appendage-bearing objects are all connected to the ground, so they could all be the same organism-- or they could be separate ones (when a small appendage-protrusion object is pulled from the ground, it comes out with thin fibers on the end of it-- but we do not know whether these fibers were attached to other fibers underground).

-the free moving organisms are most likely diffrent organisms from the groung-bound one(s), because they seem to be more autonomous. For example, when Emily blew on the eight-legged organism, it moved quickly away, and continued to move farther than the force of Emily's breath should have pushed it.

paoli.roman's picture

Paoli and Valerie's Classifications of the Organisms

While organizing and classifying the different organisms we took into consideration their habitat (where they will be able to live), their reproduction process, and their apperance (which was tied to the habitat). 

1) Land Animals (need oxygen to survive)

      a. Mammals (do not lay eggs)

          -Gorrilla, Squirrel Monkey, Wild Dogs, Kangaroo, Lion, and Humans

      b. Animals that do lay eggs

           - Eagle, American Robin, Ostrich, Owl, Salamander, Rattle Snake

2) Land and Water Animals ( can live/survive in both environments)

       a. (all lay eggs)

         -Frog, Turtle, and Penguin

3) Acquatic Animals (can only live under water)

       a. Animals with a Skeleton

           - Lobster, Cat Fish, Whale, Brown Trout, Eels

      b. Animals without a Skeleton

         - Starfish, Octopus, Jellyfish

     c. Plants

       - Coral, Sea Weed, Sea Urchin

4)  Insects

     a. Flying Insects (with legs)

       - Butterfly, Fly

     b. Non-Flying Insects (with legs and similar round shaped bodies)

        - Ischnodemus Sabulet, Cockroach, Spider

     c. Non-Flying, no legs and live "usually" underground

        - Leech, Earthworm, Flatworm: Stylochus, Flatworm: Bipalium, Garden Slug


     a. All grow out of the ground

         - Redwood, Blue Oak, Barley Grass, Fern, Rock Rose, and Mushroom

6) Non-Visible (to the naked eye) Organisms

     -Bacteria: Pseudomonas Aeruginosa, Amoeba, Eugelena Oxyuris, Volvox, E.coli, Streptococcus


We decided to go to Encyclopedia of Life and compare the Lion to what scientists have classified it as. We both classified it as an animal and mammal. Encyclopedia of Life included the lion's eating functions, skeletal functions, and life expectancy. Other groups in the Biology103 class classified it with their skeletal functions.

~Paoli Roman and Valerie Donely



sophie b.'s picture

Our group separated all of

Our group separated all of the organisms into seven main groups, some were subdivided, others were placed in between groups, essentially classified based upon the appearance of the organism. Our main groups were: 

1) Four limbed organisms

     I.  W/opposable thumbs

    II.  Large land creatures

   III.  Slimy looking organisms

            A.  Large slimy organisms

            B.  Small slimy organisms

2) Swimming organisms

3) Organisms with out limbs

4) Winged organisms

     I.  Flying

     II.  Non-flying

5) Organisms with more than four limbs

     I.  Aquatic

    II.  Non-aquatic

6) Plants/Fungi

     I.  Land Plants

         A.  Tall land plants

         B.  Small land plants

     II.  Aquatic Plants

         A.  Tall aquatic plants

         B.  Small aquatic plants

7) Organisms too small to be seen with the naked eye

There were a few organisms could not fit solely into one category, the  jelly fish, lobster, octopus, and starfish fell between categories 2 and 5,  while the eel fell between categories 2 and 3.  The butterfly and fly fell between categories 4 and 5.


The pros of our system are that it more easily lines up with everyday human experience, allowing for easy-to-memorize subdivisions between categories that mesh with the expected classification system.  The purpose of categorization is utility, and this is a useful way to categorize things if you need to make comparisons in everyday life.


The cons are that while the system makes sense for snap judgements, it is very vague, allowing for more disagreement over categorization over a more specified system.  Because we don't have tools for close examination of the organisms, close biological investigation may reveal more important links between creatures.


We believe there is some evidence of nested clumpy diversity but we need more organisms to get a more complete picture of the connections between life forms.

Terrible2s's picture

    Our classification system



Our classification system was based on first separating the organisms based on where the organism is able to dwell. We determined that there is nesting clumpy diversity within our system. We used empirical observations to classify, and based much of our system on appearance and our knowledge of similar earth creatures.
 When looking at Tree of Life website we determined that it uses a classification system based on phylogeny. This means that it's based on how things have evolved and are grouped by those similarities.


I.                    Water Dwelling

a.       Simple
                                                               i.      Single cell organisms
1.       Amoeba
2.       Euglena oxyuris
3.       Volvox
b.      Complex
                                                               i.      Fins
1.       Brown trout
2.       Channel catfish
3.       Killer whale
                                                             ii.      Legs and tentacles
1.       Jellyfish
2.       Lobster
3.       Octopus
4.       Starfish
                                                            iii.      Neither
1.       Free moving
a.       Eel
b.      Leech
2.       Stationary
a.       Coral
b.      Sea urchin
c.       Seaweed
d.      Sponge
II.                  Land Dwelling
a.       Simple
                               i.      Single cell
1.       Bacteria
2.       Streptococcus
b.      Complex
                               i.      No legs
1.       Photosynthesizing
a.       Over 1 meter
                                                                   i.      Blue oak
                                                                   ii.      Redwood
b.      Under 1 meter
                                                                     i.      Barley grass
                                                                     ii.      Fern
                                                                     iii.      Mushroom
                                                                     iv.      Rock rose
                              ii.      Bi-pedal
1.       Egg-laying
a.       Ostrich
b.      Penguin
2.       Non egg-laying
a.       Hair
                                                             i.      Humans
b. Fur
      i.      Gorilla
                                                             ii.      Kangaroo
                                                             iii.      Squirrel monkey
3.       Poly-pedal
a.       4 legs
                                                              i.      Warm blooded
1.       Lion
2.       Wild-dog
                                                              ii.      Cold-blooded
1.       Frog
2.       Salamander
3.       Turtle
b.      8 legs
                                                                i.      Spider
III.                Air
a.       Beaks
                           i.      American robin
                           ii.      Eagle
                           iii.      Owl
b.      No beaks
                            i.      Butterfly
                            ii.      Cockroach
                            iii.      Fly
                            iv.      Ischnodemus sabulet
Maria, Debbi, Anna, Terrible2s



drichard's picture

Revistiting Nearer

After updating our equipment and informing our initial observations, we returned to the distant planet Nearer to begin the classification process. Focusing on plant-life, we devised a hierarchical system of categorization so as to enable a dialogue and further study about the life on Nearer. The following is a brief summary of our system.

Beginning under the grand umbrella of plant life, we began our divisions based on plants with stalks and plants without stalks.

Plants with stalks were father divided between wooded and non wooded plants. Since most wooded plants exceeded the height of 1 meter, we mainly focused on non-wooded plants. The basic distinction between non wooded plants with stalks is whether or not these plants have leaves, or are a single blade. The next categories were based upon the thickness of either the leaves or the blades, whichever category the plants are in. Since this is somewhat subjective, plants with leaves broader than half a centimeter are not considered to have thin blades or leaves. To further distinguish between leafed plants, we added categories for small hairs on the plant body, and finally the general direction of primary growth, either upwards (away from the ground) or outwards (spreading away from a central point).

The division of the non-stalk plants (moss) began with the separation of the fibrous and leafy varieties.  To begin with the fibrous variety, we further divided this section by the thickness of the moss.  From this division, there emerged different two groups.  The fibrous moss found to be less than 1.49 cm (the first group) were classified as the species "brittle moss," and those that are over 1.5 cm (the second group) were divided into two different species the "pillow moss" and the "rug moss." Leafy moss was similarly divided. All plants under 1 cm were deemed "cactus moss" and all plants over 1 cm were deemed "ivy moss." These distinctions were made based on height while the names focused on the particular look of the plant and its potential earthly correlate.

-Dr. David A Richardson, PhD

-Julia M Stuart, = )


-Lili Elsesser

-Herman Marcia

JPierre's picture

Jennifer Pierre, Karina Granadeno, Heather Lewis, Mariah Casias

Below is our classification of the images we observed. We divided them into two overarching categories: 1) organisms visible to the naked eye and 2) organisms that are invisible to the naked eye. Next, we used a  series of classifications to further divide the categories into the aspects below.

1. Visible to the Naked Eye

     A. Root Systems

          a. Trunks

          b. Non-Trunks

     B. Non-Root Systems

          a. Vertebrates

               Land Vertebrates






               Water Vertebrates

                   -Those that have Eggs

                   -Those that have Live-Birth

           b. Non-Vertebrates

              Land Non-Vertebrates

                   -Those with Legs

                   -Those without Legs

                            *Those that are Round

                            *Those that are Linear

              Water Non-Vertebrates

                   -Those with Shells

                   -Those without Shells 

2. Invisible to the Naked Eye