Transcript Beaks of Finches - Great Neck School District

The Beaks of
Finches
NYSED Lab
Michael Comet
South Lewis High School
Turin, NY
What is the “goal” of the lab?
• Demonstrate how Darwin’s Finches
(those that he observed on the
Galapagos Islands) have adapted new
beaks yet remain similar to the shared
common ancestor that most likely
came from the mainland.
Required Supplies for “B of F”
A randomly
assigned “beak”
Small seed island
Petri dish
Large seed island
Timer
Round 1
• Only one seed at a time may be eaten. To
be “eaten” it must land inside your
stomach.
• If you scoop seeds or eat more than one
at a time, you “choke” and vomit all of your
seeds out.
• Average is taken from four trials, 60
seconds each.
And now, Round 1…
Seeds Collected
Partner #1
Trial #1
Partner #1
Trial #2
Partner #2
Trial #3
Partner #2
Trial #4
Average
Did you average over 13 seeds?
YES
Go to Round 2
Increased
Competition
NO
Repeat Round 1
on the “big seed”
island with the
same beak
Successful in Round 1?
Welcome to Round 2!!!
Repeat the same procedure but this time
have another “bird” to compete against!
Round 2 - Increased Competition
Seeds Collected
Partner #1
Trial #1
Partner #1
Trial #2
Partner #2
Trial #3
Partner #2
Trial #4
Average
Compete the table and move on to Round
3 where there is “Increased Competition” if
you average over 13 seeds.
Unsuccessful in Round 1?
Go to a “large seed” island and start over (even though you have starved to death, you are resurrected)
Seeds Collected
Partner #1
Trial #1
Partner #1
Trial #2
Partner #2
Trial #3
Partner #2
Trial #4
Average
Did you average over 13 seeds this time?
YES
Go to Round 2, but
with another large
seed eater as
competition on the
“large seed” island
NO
Get a new “beak”
and try yet again
(not a possibility
in nature)
Successful in Round 2?
Welcome to Round 3!!
Increased Competition
(more than 1 other bird)
Repeat the same procedure but
this time have even more birds to
compete against!
Seeds
Collected
Partner #1
Trial #1
Partner #1
Trial #2
Partner #2
Trial #3
Partner #2
Trial #4
Average
Don’t fret. It is almost over!
Not successful in Round 2?
“Here endeth the lesson…”
So, what did you learn?
• Birds have evolved many different mechanisms and
modifications that make them more well-adapted to
the environment in which they live.
• Structural differences (in beaks) are significant
enough to make you into a new species, but you did
descend from a common ancestor.
• The adaptations that are contribute to the most
success allow that individual to survive and
reproduce.
• The adaptations that are contribute to a lack of
success are not passed on since they either starve
or have no “breeding rights”.