By Bathgate

New York, United States

Does a dragonfly know calculus?

He only feeds on the wing. In order to intercept its prey in mid flight, it must calculate speed, distance and angle of attack.

A dragonfly, the fastest insect, can fly a distance of 50 feet at a speed of 25 feet per second. Find the time in seconds. Write the equation in the form d = rt, then solve.

- 26 Jul, 2020

### Answers

It's wonderful they can do all that. They're cleverer than me, I can just about count to ten :D

27 Jul, 2020

that is why they are so successful and have been on the planet for over 300 million years. there was a fossil of one from the Derbyshire coalfields with a wing span of over 20cm and is called the beast of Bolsover [not to be confused with the MP with the same name.

https://www.visit-nottinghamshire.co.uk/whats-on/the-bolsover...

there are some amazing videos of them hunting too.

27 Jul, 2020

Well, it's cleverer than me, I definitely can't do the sum!

Like Hywel, I can count up to 10 ( also in German & French)

but that doesn't help with the maths, or math as they say in th USA.

27 Jul, 2020

Are you asking how long it takes? 2 seconds, no equation needed. . And our cat managed to catch one without falling in the pond... Or have I missed the point?

27 Jul, 2020

that's because you have actually learnt to do the sum with out knowingly using the equation Stera.

Must say though that in the UK the formula is d = st where s is speed in metres/second if you have to use the SI units. though we use miles per hour [mph] on the roads still. aren't we quaint haha?

We really do mix and match imperial with metric. In quilting the fabric is 44" wide but sold by the metre.

27 Jul, 2020

I resist metric wherever possible and use my age as as excuse. Most shops here happily sell imperial or metric to suit the customer. But this one is so simple really - there are two 25s in 50. It flies 25 feet in 1 second so it takes 2 seconds to fly 50 feet.

27 Jul, 2020

It's a little more complex and wonderful than that Stera. Here, I'm giving you the data to work with and you can simply plug in the numbers on one of those internet calculators or a formula you have learned in school.

A dragonfly must acquire it's own raw data from it's own coordinates - from it's currant location to catch a moving target. How does it know what its coordinates are? Do you know your own coordinates right now? (Longitude and Latitude) After acquiring the raw data of a mosquito flying around over there by the bird bath, the dragonfly must anticipate exactly where that mosquito is going to be in 2.7532 seconds (the time it will take to reach its target). Only then he can formulate a plan of attack - to intercept the mosquito in mid flight. All of this raw data must be calculated raw whenever the dragonfly wants to eat. He does not eat off the ground or vegetation or anything dead. He has a 95% accuracy rate (hitting the target...eating...staying alive, existing for 300 million years, Eileen!). That's Acing the American Bar Exam, the Dean's List..an Olympic Gold Medal, the Masters, winning the Triathlon everyday. What's your batting average? Do you play baseball? Tennis?

30 Jul, 2020

Tug that certainly puts things into perspective - I've leaned to type in Junior High school and I hated it. It was an old steel Royal mechanical typewriter. It weighed a ton. Man your fingers got a helluva workout pushing those spring loaded mechanical metal keys. I went to St. Mary Magdalene Parish School. The school didn't have money for electric typewriters so we used all steel mechanical typewriters. Now I can type in the dark at lightening speed. If I consciously thought about what each of my fingers was doing on the keyboard while typing, I would end up with this: a';guewoutg'aug; oawjg;lo u.

I'm still amazed that this little bug can kick my butt in math. That's all I wanted to say.

Eileen: I'm accustomed to the Imperial System and have difficulty converting over to the Metric System. I try to relate the metric system to the Imperial System but it really doesn't. I was told in grade school that the USA was converting to the metric system but it never happened...not officially anyway.

30 Jul, 2020

Fortunately for the dragonfly he doesn't have to do the calculations! Brains are amazing aren't they?

30 Jul, 2020

Yep that's for sure. Difficult to fathom.

30 Jul, 2020

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One of nature's wonders, Bathgate! For perspective, though, humans perform equally complex and time sensitive calculations every minute, just in the process of walking running, reaching, or even typling...er, I mean typing! :} It's just as well that all that is mostly subconscious, or we would be spending far more time face planting than we do already. One of the acrobats at our local Renaissance Festival used to ask the front rows of his audience if they liked the show, or if they were too busy doing rapid vector analysis--trying to determine if he was going to fall on them, of course!

27 Jul, 2020