Little Aliens-L-M
Name_________________________________ Period_______
You are part of a team that has discovered life on another planet! Part of your job is to
group and classify the newly discovered aliens. Follow the guidelines below to classify your
twelve aliens by creating a dichotomous key.
1. Lay out your twelve alien cards on your desk so you can see them all clearly. Notice how
each alien is different from all the others, and how the scientific name for each alien is
written out below the alien in the bottom left corner of the card.
2. One major difference between the 12 aliens is the number of eyes each alien has. They
have anywhere between one and four eyes and so we will first separate all of the aliens
by the number of eyes they have. For Number 1a on the dichotomous key (on the next
page) write “Has one eye” and for Number 1b, write “Has more than one eye”. We are first
going to look at the aliens with only one eye, so at the end of the 1a line on the
dichotomous key write “Go to 2”. We now need to find a characteristic that differentiates
the two organisms with only one eye (Cyclops hattus and Cyclops alien) and then write out
that difference on lines 2a and 2b. One major difference is that Cyclops hattus is wearing a
hat while Cyclops alien is not. So on line 2a write “Is wearing a hat” and then write
“Cyclops hattus” at the end of that line. Then, on line 2b, write “Is not wearing a hat” and
then write “Cyclops alien” at the end of that line. Since both Cyclops hattus and Cyclops
alien have been classified in the dichotomous key, we do not need to use them anymore.
Set the cards off to the side since we will not be using them anymore in making the key.
3. Now, looking back to line 1b, all of the aliens that are left have more than one eye. We
need to find one difference between these ten remaining aliens that puts each alien into
one of two categories. Since we already used the number 2 slot on the dichotomous key,
this difference will be shown on number 3a and 3b on the key. Therefore, write “Go to 3”
on line 1b. One major difference between the remaining aliens is that they either have
ears or do not have ears. Write “Has ears” on line 3a and “Does not have ears” on line 3b.
We will look at the aliens that have ears first and so write “Go to 4” on line 3a. The two
aliens with ears are Pretty earus and Ladyus earus. One major difference between the two
is that Ladyus earus has hair and Pretty earus does not. Write out this difference and the
scientific names on lines 4a and 4b. Set the two alien cards aside so that they are not used
any longer.
4. Now, write “Go to 5” on line 3b. For 5a and 5b, find something that separates the
remaining eight aliens into two categories and write that difference on the two lines.
Continue the process of creating a dichotomous key as was done in steps 1-3 and
classifying the organisms until all of the aliens are classified. Remember to set aside all
aliens that are classified so that you do not accidentally classify them twice.
Dichotomous Key:
1
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
2
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
3
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
4
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
5
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
6
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
7
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
8
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
9
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
10
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
11
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
12
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
13
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
Little Aliens-H
Name_________________________________ Period_______
Part 1: You are part of a team that has discovered life on another planet! Part of your job is
to classify the aliens so when you are speaking with people from other countries, you will
be on the same page. Your job is to create a dichotomous key where you classify all twelve
aliens according to their various characteristics. Use the template provided below to create
your dichotomous key. **Note that the scientific name of each alien is located on the
bottom left-hand corner of each card. Also, once you have classified a species, set that alien
card off to the side since you no longer need to use it.
Dichotomous Key Template:
1
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
2
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
3
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
4
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
5
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
6
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
7
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
8
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
9
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
10
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
11
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
12
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
13
a. _____________________________________________________________________________________________
b. _____________________________________________________________________________________________
Part 2: Now that you have created a dichotomous key and classified all twelve of the aliens,
choose seven aliens and create a cladogram in the space below where you group and
organize the aliens based off of their derived characteristics.
**Note: It might be helpful to create a table where you organize the derived characteristics
of the seven aliens you choose. If you create a table, attach it to the back of this packet.