# 3.14 Ways to Make Pi Day a Piece of Cake!

Celebrated each year on March 14th (3.14), Pi Day commemorates the irrational, transcendent, and never-ending ratio that’s used to represent a mathematical constant. This infinite number is crucial when describing circles because no matter how big or small, the ratio of a circle’s circumference to its diameter will always equal to pi.

In 2009, pi day, also written π or 3.14, was declared an official national holiday–one that’s worth celebrating! We’ll help you kick things off with 3 fun facts, 1 joke, and 4 activities that are certain to get you in the Pi Day spirit.

Continue reading “3.14 Ways to Make Pi Day a Piece of Cake!”

# Counting Crows: Evidence for Hard-Wired, Inborn Ability to Detect Numerical Sets

“The Great Book of Nature is written in mathematical language” –Galileo Galilei (1)

If mathematics is the language of the universe, might we find the ability to do math hard-wired in species?

Research in primates has demonstrated that even without training, humans and monkeys possess numerosity, the ability to assess the number of items in a set (2,3).

A paper in Current Biology from Wagener and colleagues provides evidence that crows are born with a subset of neurons that are “hard wired” to perceive the number of items in a set (4). This work provides yet more evidence supporting a hypothesis of an innate “number sense” that is provided by a specific group of “preprogrammed” neurons.

In this study, Wagener’s group measured the responses of single neurons in two “numerically naïve” crows to color dot arrays. They measured neurons in the endbrain region known as the niopallium caudolaterale (NCL), which is thought to be the avian analog of the primate prefrontal cortex. They found that 12% of the neurons in NCL specifically responded to numbers and that specific neurons responded to specific numbers of items with greater or lesser activity.

This is the first such study to investigate the idea of an innate “sense of number” in untrained vertebrates that are not primates, and as such it suggests that a hard-wired, innate “sense of number” is not a special feature of the complex cerebral cortex of the primate brain but is an adaptive property that evolved independently in the differently structured and evolved end brains of birds.

Many questions remain. Are there similarities in the actual neurons involved? What does learning do on a physiological level to these neurons: Increase their number, increase connections to them?  What other vertebrates have similar innate mechanisms for assessing numbers of items? What about other members of the animal kingdom that need to have a sense of number for social or foraging behavior? How is it accomplished?

And finally, one last burning question, if birds are dinosaurs, does that mean that dinosaurs perished because they didn’t do their math homework? Asking for an eleven-year-old I know.

1. Tyson, Peter. (2001) Describing Nature with math. NOVA  http://www.pbs.org/wgbh/nova/physics/describing-nature-math.html
2. Izard, V. et al. (2009) Newborn infants perceive abstract numbers PNAS USA 106, 10382–85.
3. Viswanahtan, P. and Neider, A. (2013) Neuronal correlates of a visual “sense of number” in primate parietal and prefrontal cortices. PNAS USA 110, 1118–95.
4. Wagnener, L. et al. (2018) Neurons in the endbrain of numerically naïve crows spontaneously encode visual numerosity Cur. Biol. 28, 1–5.

# Pop Pi Quiz

Teachers, architects and engineers have found the mathematical constant, π, to be an invaluable tool for understanding and changing the world around us. Without Π, we would not be able to quickly calculate the area of a circle. To celebrate Pi Day (March 14th), today’s mental exercise will be to test your knowledge of Π. Are you ready for more Π?

1) What does Π represent?
a) The ratio of the circumference of a circle to its diameter
b) A rounded value of 3.14
c) The 16th letter in the Greek alphabet
d) All of the above Continue reading “Pop Pi Quiz”