Spit: What's Cool About Drool, written by Mary Batten. A Firefly Book, 2019. $12.95 ages 9 and up

"You don’t have to think about producing spit. Your body does it automatically. Signals from your brain tell the salivary glands to do their things. That’s because they are connected to your autonomic, or involuntary, nervous system – of which your brain is the control center. This system also keeps you breathing and your heart pumping, without you giving it a second thought."

This book will find fans with the younger set, when it is shared with them. Who doesn't want to know all there is to know about spit? We know what most adults think about it. Gross! However, it is definitely written with both middle and high school students in mind.

I rarely think about spit except when I watch sports. Then, I mostly find the habit very unappealing. To each their own, I guess. What Mary Batten does for her readers is fully describe saliva and its benefits to our bodies. We could not swallow, eat of talk without it.

"Outside your body, spit can seem
like a nasty, slimy blob. But inside
your mouth, it does some important
things."

Spit is not only important to us. It is also important to a variety of animals; and, to scientists who use it to help them with research into cures for some devastating diseases. Now that you know that, Ms. Batten will go on to offer much more data to digest.

She begins with what is in our mouths and moves on to describe chewing and how it is done from species to species. Our spit contains information about our genetic makeup and can help to identify us. By analyzing spit, coaches and doctors can determine the health of their athletes. As spit can reveal many things about humans, it does the same for animals.

"Spit tests are perfect for zoo animals. Blood tests
are difficult to collect, and they're uncomfortable,
just as they are for people. Collecting spit is minimally
invasive and takes advantage of something the animal
has already been trained to do."

The comprehensive information is provided in 11 chapters, each one filled with boxes and revealing captions specifically describing how spit helps, protects, and even captures prey. The book ends with a chapter called Spitting For Sport, and includes a list of cricket spitting rules. Remember that you will need a brown house cricket if you want to participate.

"World Record Pit Spit

According to Guinness World Records, an American man set a new world record when he spat a cherry pit 93 feet and 6 1/2 inches (28.51 meters) in 2004 at the International Cherry Pit-Spitting Championship. That spit is really incredible. It's almost as long as an NBA basketball court!"

Fascinating, well-designed and very accessible for its conversational, often humorous, tone, this is a book that would make a useful addition to all school and classroom libraries.