Taxonomy and Evolution Lab

Taxonomy and Evolution Lab
Caminalcules
In this lab you will do two things with a group of imaginary organisms called Caminalcules:
1) develop a taxonomic classification and
2) reconstruct an evolutionary tree.
You will have pictures for 14 “living” and 58 “fossil” species. Take a look at the pictures and
note the variety of appendages, shell shape, color pattern, etc. Each species is identified by a
number rather than a name. For fossil Caminalcules there is also a number in parentheses
indicating the geological age of each specimen in millions of years. Most of the fossil
Caminalcules are extinct, but you will notice that a few are still living (e.g. species #24 is found
among the living forms, but there is also a 2 million year old fossil of #24 in our collection).
First, using the 14 “living” species, create a taxonomic classification down to the genus level.
The Caminalcules are all members of the same phylum, so your first separations would be into
Classes. Continue classifying each species through Order, Family, Genus, and Species. Write
your taxonomic key on the top of your butcher paper.
Also, include your reasons for separation in your taxonomic key. You will be graded for using
good reasoning in your dichotomy.
Order 1
12 spots
Phylum Caminalcula
Class 1
Round head
Class 2
Square head
Order 2
13 spots Order 3
101
Long tail
Family 1 Family 2 Family 3
Genus 1
Genus 2
Long arms
Genus 3
Short arms Genus 4
102
Short tail 103 104 105
Warning: Do not separate similar species too early! Look how similar 13 and 14 are to each
other. They should not separate until genus or species level. You do not have to dichotomize
until you feel they are different enough. The above example may help. Understand that this
is only an example. You separate the “bugs” as you think is appropriate. Though there is no
wrong answer, your classification must make sense.
DO NOT GLUE THE LIVING SPECIES ON!!!

Second part
Now make 20 equally spaced horizontal lines on your butcher paper starting just under your
taxonomic key (about 2” apart is a good spacing). These lines represent the past 19 million
years to the present, so write 19 next to the bottom one, 18, and so on to Present Day. You will
now construct the history of the Caminalcules by placing them in their evolutionary order to see
if your taxonomic key works.
Advice:
• Use the numbers in parentheses to know how
old the species is; the living species do not have
parentheses and will end up in Present Day.
• Start at the bottom (oldest) and work up.
• The numbers were assigned randomly; there are
no clues in the numbers.
• Don’t glue your pieces until you know the whole
thing is right, and then draw lines to show the
evolution. Here is an example --------------
• There may be missing fossils in the chain, and
not every line finishes at the top. Just make
sure the years on the fossils are on the right
lines.
• You are allowed to skip lines when drawing the
evolutionary lines. All the species in one line do not have to evolve from the species in
the previous line. They may have come from several lines before.
• There is only one right answer for the evolutionary tree; look carefully to see the
evolutionary sequence.
After all the pieces are glued, choose three places that speciation occurred. Write a brief
reason why that population separated to form two species. You must give an example of a
behavioral barrier, a geographical barrier, and a physiological barrier.
On the back of the paper, write an explanation of why your taxonomic key did not agree with
the fossil record and what this means about classification.
You will turn in your finished taxonomic key, the fossil record, 3 explanations of speciation, and
an analysis comparing your taxonomic key with the fossil record. Worth 50 points.