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Aliens From Earth: When Animals and Plants Invade Other Ecosystems

Fall 2006 - Adopted by the New York City Public Schools in support of the science requirement for the study of ecosystems. ALIENS FROM EARTH is now in every 4th grade library in every public school in the five boroughs of New York City.

2006 Izaak Walton League of America Conservation Book of the Year Award

"Every Elementary and middle school in the country needs this wonderful book!"
Elizabeth C. Petersen
Past-President, Science Teachers of Missouri
Chair, District Science Curriculum Committee
Ladue Middle School
St. Louis, MO

"From the book title and first line of text to the information-packed, full-page color illustrations, this overview of ecological missteps is nonstop intriguing."
Booklist

". . . an excellent introduction to exotic invasives for third through sixth grade students. . . . This book does a very good job of explaining a complex topic in a thought-provoking, non-frightening way and offers concrete ways that readers can think globally and act locally. . . Aliens from Earth would be a great addition to any elementary school library."
National Science Teachers Association

"Visually striking and readable . . . The examples throughout are thought-provoking, the illustrations outstanding, and the concluding words on steps to take to keep aliens out are helpful and practical. . . . Fascinating."
Kirkus Reviews

"Aliens from Earth does an excellent job of encouraging renewed respect for biodiversity and the delicate balance of life in our ecosystem."
Midwest Book Review


Living things have been traveling from one place to another for millions of years. Until recently, travel was very slow. Animals walked, flew, and crawled across ancient land bridges from one continent to another. Carried by wind, water, birds, and other animals, seeds moved from place to place. Over hundreds of thousands of years, some aliens fit into ecosystems and became part of the web of interrelationships that enable a variety of different species to live together.

Today, alien invasion occurs at jet speed and is a major threat to biodiversity. Homo sapiens, the species to which all modern humans belong, first appeared in Africa. As their numbers grew, people began to need more natural resources, and eventually they moved into places where human beings had never lived before. They, too, were aliens in these new surroundings. Wherever people settled, they changed the habitat. They hunted animals, gathered native plants, and learned to farm.

Over the centuries, people invented ways to move around faster and to go longer distances. Suddenly, the oceans were no longer barriers to alien invaders. When people began traveling by ship, they took animals like goats, dogs, cats, and chickens with them. They took seeds of plants they liked to eat. Some of these new animals and plants, such as horses, wheat, and corn helped people in their new environment, but many did not. Without meaning to, people also brought pests. The ancestors of the brown rats that now infest many of America’s cities arrived as stowaways on the ships bringing the first Europeans to North America.

Today every living thing imaginable—viruses, bacteria, insects, plants, sea creatures—travels on the same planes and ships that carry people and cargo. And when we carry new species of plants or animals into a different habitat, we may disturb the delicate balance within that ecosystem.

Beautifully illustrated by artist Beverly Doyle.