It’s a dog-eat-dog world and inside a sand tiger shark’s womb, it’s a shark-eat-shark world. While inside the womb, baby sand tiger sharks duke it out with their fellow unborn baby tiger shark siblings to be the lone victor (and only child) in this real life Hunger Games battle to the death.

In a report by National Geographic, Ed Yong discusses new information about sand tiger sharks gathered from a new study.

“The first embryo to emerge in each uterus—the ‘hatchling’—always cannibalises its younger siblings. It’s so voracious that at least one scientist has been bitten by a sand tiger pup while unwisely sticking a finger in a pregnant female’s uterus.”

From their diet of nutrients from its mother and the bodies of their siblings, these cannibalistic sharks emerge from the womb at a size that is big enough so that they can protect themselves from predators. Makes you re-think your own sibling rivalry a bit.

Check out more on sharks and animal family life from PUP!

1. A Natural History of Families by Scott Forbes

Why do baby sharks, hyenas, and pelicans kill their siblings? Why do beetles and mice commit infanticide? Why are twins and birth defects more common in older human mothers? A Natural History of Families concisely examines what behavioral ecologists have discovered about family dynamics and what these insights might tell us about human biology and behavior. Scott Forbes’s engaging account describes an uneasy union among family members in which rivalry for resources often has dramatic and even fatal consequences.

In nature, parents invest resources and control the allocation of resources among their offspring to perpetuate their genetic lineage. Those families sometimes function as cooperative units, the nepotistic and loving havens we choose to identify with. In the natural world, however, dysfunctional familial behavior is disarmingly commonplace.

While explaining why infanticide, fratricide, and other seemingly antisocial behaviors are necessary, Forbes also uncovers several surprising applications to humans. Here the conflict begins in the moments following conception as embryos struggle to wrest control of pregnancy from the mother, and to wring more nourishment from her than she can spare, thus triggering morning sickness, diabetes, and high blood pressure. Mothers, in return, often spontaneously abort embryos with severe genetic defects, allowing for prenatal quality control of offspring.

Using a broad sweep of entertaining examples culled from the world of animals and humans, A Natural History of Families is a lively introduction to the behavioral ecology of the family.

2. Sharks of the World by Leonard Compagno, Marc Dando, & Sarah Fowler

Everyone’s heard of the Great Whites. But most people know little of the hundreds of other types of sharks that inhabit the world’s oceans. Written by two of the world’s leading authorities and superbly illustrated by wildlife artist Marc Dando, this is the first comprehensive field guide to all 440-plus shark species. Color plates illustrate all species, and detailed accounts include diagnostic line drawings and a distribution map for each species. Introductory chapters treat physiology, behavior, reproduction, ecology, diet, and sharks’ interrelationships with humans.

The weather is great, the sun is shining, the birds are chirping, and soon, the cicadas will be chirping, too. This year marks the end of a 17 year long life-cycle for the cicada genus magicicadas in the Northeast. After spending nearly two decades burrowed in the ground as nymphs, they are slated to spring out of the ground to mate and lay eggs for the next generation of cicadas.

These cicadas are part of the North American genus magicicadas that have one of the longest life spans of all insects. If you are near any place that has trees that have not been disturbed for the past 17 years, you can expect many cicadas to be flying around soon- though they will be flying around everywhere soon enough! When the ground reaches a toasty 64 degrees, cicadas that have burrowed deep in the ground around trees will emerge. Scientists are reporting that billions of cicadas will emerge very soon with the warm weather.

Many are dubbing the return of the cicadas as “Swarmageddon” because of the number of cicadas that are expected to emerge. Cicadas are harmless and won’t bite or sting you, though their loud buzzing noises (some as loud as a subway) will let you know that they have arrived.

As you wait out the cicada-storm, check out these PUP books on bugs!

1. Bugs Rule!: An Introduction to the World of Insects by Whitney Cranshaw & Richard Redak

Bugs Rule! provides a lively introduction to the biology and natural history of insects and their noninsect cousins, such as spiders, scorpions, and centipedes. This richly illustrated textbook features more than 830 color photos, a concise overview of the basics of entomology, and numerous sidebars that highlight and explain key points. Detailed chapters cover each of the major insect groups, describing their physiology, behaviors, feeding habits, reproduction, human interactions, and more.

Ideal for nonscience majors and anyone seeking to learn more about insects and their arthropod relatives, Bugs Rule! offers a one-of-a-kind gateway into the world of these amazing creatures.

Another book by Cranshaw that is currently available features an entire chapter on cicadas among many other bugs.

2. Garden Insects of North America: The Ultimate Guide to Backyard Bugs by Whitney Cranshaw

Garden Insects of North America is the most comprehensive and user-friendly guide to the common insects and mites affecting yard and garden plants in North America. In a manner no previous book has come close to achieving, through full-color photos and concise, clear, scientifically accurate text, it describes the vast majority of species associated with shade trees and shrubs, turfgrass, flowers and ornamental plants, vegetables, and fruits–1,420 of them, including crickets, katydids, fruit flies, mealybugs, moths, maggots, borers, aphids, ants, bees, and many, many more. For particularly abundant bugs adept at damaging garden plants, management tips are also included. Covering all of the continental United States and Canada, this is the definitive one-volume resource for amateur gardeners, insect lovers, and professional entomologists alike.

To ease identification, the book is organized by plant area affected (e.g., foliage, flowers, stems) and within that, by taxa. Close to a third of the species are primarily leaf chewers, with about the same number of sap suckers. Multiple photos of various life stages and typical plant symptoms are included for key species. The text, on the facing page, provides basic information on host plants, characteristic damage caused to plants, distribution, life history, habits, and, where necessary, how to keep “pests” in check–in short, the essentials to better understanding, appreciating, and tolerating these creatures.

Whether managing, studying, or simply observing insects, identification is the first step–and this book is the key. With it in hand, the marvelous microcosm right outside the house finally comes fully into view.

For more on cicada-watch 2013, Radiolab has a cool interactive map that is tracking cicada sightings along the East Coast. You can also check out this article over at New York Daily News for more information on the cicadas.

Have you seen any cicadas in your area?