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How Birds Stick Together

by Derek Stump

Sometimes the smallest animals (like people) have the biggest attitudes. It’s especially true for birds. Little penguins sneak into sushi restaurants. Seagulls will pluck your lunch right out of your hands. And now there’s this bold blackbird. It chased a much bigger osprey away from its nest, then took a ride on the stick the osprey was carrying. Look at the blackbird hanging onto the back end! The person who took the picture couldn’t believe how long the little bird chased the bigger one. So of course it needed a rest. We hope it made it back home!


Wee ones: If there are 3 baby birds and 1 mom bird in a nest, how many birds is that?


Little kids: If the blackbird chased the osprey for 4 minutes, then sat on the branch for 2 minutes, how much longer did it chase than sit? Bonus: An osprey’s wingspan can be up to 6 feet wide! How big is your wingspan? Stretch your arms wide and have a grown-up measure – is it more or less than 6 feet?


Big kids: If this blackbird weighed 2 ounces, and the osprey weighed 2 pounds… how many blackbirds would it take to equal the weight of 1 osprey? (Reminder: A pound has 16 ounces.) Bonus: What if you wanted the osprey to pick YOU up and give you a ride? How many blackbirds’ worth do you weigh? Find out your weight in pounds (or guess)!


The sky’s the limit: If a bunch of those 2-ounce blackbirds and 2-pound ospreys weigh 12 pounds all together, and there are 28 more blackbirds than ospreys, how many of each bird are on the scale?

Answers:

Wee ones: 4 birds.


Little kids: 2 minutes longer. Bonus: Different for everyone, but we bet your wingspan is less than 6 feet!

Big kids: 16 blackbirds – 8 blackbirds to make 1 pound. Bonus: Different for everyone…find your weight in pounds, then multiply by 8 since each pound is the same as 8 blackbirds! (You could also find your weight in pounds, multiply by 16 to get ounces, then divide by 2…but multiplying by 16 and dividing by 2 is the same as multiplying by 8).


The sky’s the limit: 4 ospreys and 32 blackbirds. The fastest way to do this is with algebra: we have B blackbirds and S ospreys, and B = S + 28, and their total weight is 12 x 16 = 192 ounces. So:

32S + 2B = 192 ounces

32S + 2 x (S + 28) = 192

32S + 2S + 56 = 192

34S + 56 = 192

34S = 136

S = 4, so B = 32

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