Biology 11A Lab #11 Poster article and keying
specimens with a dichotomous key
No pre-lab for this lab. Come prepared to find an article for your poster presentation at the end
of the semester. We will bring out laptops if you do not have a device that can search the
internet. You will need to find an article that interests you and that you can use for your poster at
the end of the semester.
Choosing an article for your final poster:
Google Scholar may be the best place to start. This is a site that carries scientific literature
and often has pdfs of an article that you would otherwise need to buy. DO NOT BUY AN
ARTICLE. The library has many, and if they don’t have them, then they can get them for you in
a couple of days. PLOS is another good source. It stands for Public Library of Science and
provides articles for free. Your text has articles at the end of every chapter. You can pick one of
those if you wish. In general, you should not try to conquer just “any” article that you
encounter. Browse through some articles and then decide whether or not to give it further
attention. The decision is based on several factors:
1) Whether you can understand it!
2) Whether the article is of sufficient interest
3) Whether the article is relevant to our class
4) Whether the article is clearly written and accessible at least after reasonable amount of
effort
5) Whether the article is "meaty"
6) Whether the article is within a reasonable length.
Phase I: Screening the article
1) Read the title once fast looking for key words. Read the title slowly until it makes sense.
2) Some articles have a brief list of key words. Although they are sometimes misleading (as
anyone who has done a computer reference search knows) they are usually quite informative and
should be looked at early on.
3) Can you understand it?
Once you think you have found a journal article to review, then run it by me and I will approve it
or instead suggest that you look some more. If your article is approved, move on to using a
dichotomous key to identify four insects.
Using a dichotomous key (in pairs)
A dichotomous key is used for the identification of organisms based on a series of choices
between alternative characters.
First see the simple YouTube (2:38) on Dichotomous Keys:
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&ved=0ahUKEwjcgfTK
67nLAhVHx2MKHbOlCRwQtwIINDAG&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv
%3DM51AKJqx-7s&usg=AFQjCNFDV1BQ69wvWYfQMAmqb64VF9gZqQ
Key out four insects from a box of pinned bugs made available to you. I have collected these at
different locations and they may be very familiar to you (lady bugs, wasps, flies and crickets).
You know the common names, but I want you to find the scientific name.
1.
Use a cork to stab your first insect pin onto and place it on the stage of a
dissecting scope . Using a cork will free up your hands to use the dials of
scope allowing you to focus on the insect.
2.
Your job is to select one of the dichotomous key provided in lab and find the scientific
name to the insect you picked. You will have to list the steps (for me!), so keep track of
this and write it down. Always return the pinned insects to the box when finished. Be
gentle with them for they will crumble.
3.
In order to see some of the very hidden structures on the bugs, you will have to flip the
pin and insect, and insert the pin perhaps upside down on the cork.
4.
Be prepared to rotate the pin quite a few times in order to visualize the structure the key
asks you to find.
5. By the end of the lab you should have identified the Order, Family, Genus and species of
four insects. The wasps are of different species, so you may choose to identify three
wasps and one other insect if you wish.
6.
You will hand in a sheet of paper that
Part 1: Tells me the complete name of the article you found; author of the article
and mane of the journal where it is published.
Part 2: Has 4 insects identified like this:
a. Common name __________________________
b. Order __________________________________
c. Family _________________________________
d. Genus __________________________________
e. species _________________________________
Steps it took to get to the highest keyable stage:
1.
2.
3.
4.
5.
6.
_ex: winged_____________________
_______________________________
________________________________
_______________________________
_______________________________
________________________________
Before you leave, make sure you have the POSTER guidelines.