Review of Just the Right Size, by Nicola Davies

Just the Right Size

Why Big Animals Are Big and Little Animals Are Little

by Nicola Davies
Illustrated by Neal Layton

Candlewick Press, 2009. 61 pages.
Starred Review

I think this book is so cool! It explains the math and geometry behind the sizes of living creatures in a way that is clear, easy to understand, and completely memorable.

Here’s the text on the opening page of the book:

“In comics and movies, superheroes zoom across the sky, run up wall, lift things as big as buses, and use their powers to fight giant monsters!

“It’s all very exciting, but it’s a complete load of nonsense. Real humans can’t fly, hang from the ceiling, or even lift things much bigger than themselves . . . and real giant animals couldn’t exist, since they wouldn’t be able to walk or breathe.

“In fact, there are very strict rules that control what bodies can and can’t do. These rules keep creatures from getting too big, and because of them the real superheroes are usually small — a lot smaller than humans.”

The basic rules she talks about come from the math of three-dimensional objects. If you double an object’s length, its cross-section will have an area four times bigger (since it’s squared), and its volume will be eight times bigger (since it’s cubed). The authors show this beautifully with plenty of illustrations.

Now I knew about this math, but I hadn’t thought about the repercussions in regard to living creatures.

They start by looking at flight. It’s easy for a fly to take off. But if you were to double the dimensions of a fly, suddenly its wings would be four times bigger. That’s a problem, because its volume is 8 times more, so it weighs eight times more than before, so the wings aren’t going to be big enough to get it airborne.

“This is why heavier insects, like dragonflies, need very big wings to get them off the ground, and birds need huge chest muscles and large, feather-covered wings.

“But wings and muscles can’t keep up with heavier and heavier bodies. That’s why really big birds like ostriches and emus can’t fly and walk instead, and why the only way humans can fly is with the help of engines.”

Next they look at insects that can walk on water and animals that can walk on the ceiling. This has to do with surface area related to volume. Again, if the surface area gets bigger, the volume gets bigger much faster.

This is also why we can’t lift buses. Our muscle strength depends on the cross-section size of our muscles, but weight depends on volume. A rhinoceros beetle can carry 850 times its own weight on its back, but humans sure can’t do that.

I love the author’s little story that illustrates why we can’t have mega-giants and giant spiders:

“Once upon a time there was a giant who was just like a normal human, only ten times bigger all over: ten times taller, wider, and deeper, making him one thousand times heavier. The giant took his first giant step, and with a giant crashing sound, both his legs snapped. The end. (And exactly the same thing happened to the giant’s best friend, the monster spider!)”

The illustrations accompanying this story are especially fun!

And so it goes. The book goes on to look at how you need room for enough internal organs to take care of the business of life, especially surface area in the lungs.

And there are more implications of size: Being able to stay warm, being able to digest things, being able to hide from predators, and so many more things.

The only down side to reading this? This book may dampen my ability to write fantasy stories about flying unicorns or dragons. But those are fantasy anyway, right?

With its clear explanations and fun cartoon illustrations, this book will make you look at the world with new eyes. A wonderful book for budding scientists, but also for anyone interested in the world around them — like me!

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Source: This review is based on a library book from the Fairfax County Public Library.

Review of The Frog Scientist, by Pamela S. Turner

The Frog Scientist

by Pamela S. Turner
Photographs by Andy Comins

Houghton Mifflin Books for Children, Boston, 2009. 58 pages.
Starred Review

Here’s a wonderful book that presents a real-life science experiment and a successful scientist to upper elementary through middle school kids. The stunning, colorful photographs, including many different species of frogs, all nicely labelled, would draw anyone into this book.

The book begins with Tyrone Hayes, the frog scientist, and a group of his graduate students, catching frogs from a pond in Wyoming. The pictures of this show a playful side of science!

As the book goes on, it explains in detail the scientific method and the specific experiment Tyrone is carrying out in order to see if the pesticide atrazine causes male frogs to produce eggs instead of sperm. Along the way, it tells about Tyrone and how he became a research scientist.

I love that Tyrone and his students come from many different ethnic backgrounds. It’s not commented on in the text, but you can see from the pictures that science is definitely not just for white males. I love that this is just assumed and not commented on. I love that kids from minority groups can see someone who looks like them successfully doing science.

But that’s by no means all there is to love about this book. As I said, the pictures will draw the reader in, and this is a nice accessible way to introduce the scientific method in an interesting, real-life experiment that could have repercussions regarding our own health.

The story is beautifully and clearly presented, and will give kids a good look at the job of a research scientist — one they might not have ever thought of before.

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Review of Never Smile at a Monkey, by Steve Jenkins

Never Smile at a Monkey

And 17 Other Important Things to Remember

by Steve Jenkins

Houghton Mifflin Books for Children, 2009. 32 pages.
Starred Review
Sonderbooks Stand-out 2010: #4 Children’s Nonfiction

I’m a huge fan of Steve Jenkins’ art work. He uses cut paper, and is able to make animals that to me look completely realistic. His textures mimic fur or scales or feathers so thoroughly you want to touch the soft-looking ones.

But you probably shouldn’t touch any of the animals in this book. Never Smile at a Monkey is essentially a list of 18 ways certain animals can kill you or severely hurt you.

For example, the author advises you never to harrass a hippo, jostle a jellyfish, or step on a stingray. All of those creatures are capable of killing human beings. Some of the animals in this book are dangerous in surprising ways.

This is definitely not a book for very young children who might be frightened. But certain school-age children will find these facts gruesomely interesting. And, as I said, the pictures are amazing.

And, by the way, why shouldn’t you smile at a monkey?

“If you smile at a rhesus monkey, it may interpret your show of teeth as an aggressive gesture and respond violently. Even a small monkey can give you a serious bite with its long, sharp fangs.”

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Review of Dogs and Cats, by Steve Jenkins

Dogs and Cats

by Steve Jenkins

Reviewed February 5, 2008.
Houghton Mifflin, Boston, 2007. 40 pages.

This book is a delight to read, if only for the amazing intricate detail of Steve Jenkins’ cut-paper illustrations. A Caldecott winner for Actual Size, his art work is stunningly life like.

This book features interesting facts about dogs on one half. Flip the book over to learn interesting facts about cats. The illustrations show many different breeds, types, and behaviors.

Anyone will enjoy browsing through this book. It’s a perfect way to intrigue an elementary-age child with the wonders of nonfiction.

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