Sunday, November 1, 2009

Path of the jaguar: some of the world's biggest cats surprise scientists by finding their way through the human landscape.(earth science)(Cover story) USA, LLC

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Jaguars are among the best predators in the world. Their jaws are strong enough to crush a wild pig's skull. They can drag a dead cow to the top of a tree. They can see in the dark, swim in raging rivers, and pad within feet of humans without making a sound.

So what does such a fierce animal need most? Our protection, says zoologist Alan Rabinowitz. Rabinowitz heads Panthera, a group that aims to save wild cats.


"When you find an area that has jaguars, you know it is an [unspoiled] area," Rabinowitz says. "If you protect areas with jaguars, you protect many other things as well"--things like monkeys, tapir, wild pigs, crocodiles, and many other animals. Toss in the area's soil, trees, and plants, and you have the jaguar's habitat. It can be found from Argentina to northern Mexico and it features abundant prey, water, and plenty of places for jaguars to hide.

Rabinowitz has worked for decades to preserve jaguar habitat. He helped convince the government of Belize to set up the world's first jaguar sanctuary. Other populations of jaguars live in unprotected forests. On a map, places where jaguars live look like dots--"islands" of healthy habitat--spread throughout Central and South America (see map, page 9).

"Today, the biggest threat to jaguars is simply [human] population growth," Rabinowitz says. South America's population is growing fast. More people mean more deforestation to make room for houses, farms, and roads. The result: Fewer wild places. Jaguars have lost more than half their habitat in the last 100 years.

The remaining dots of protected habitat and wild land won't be enough to save the jaguar, Rabinowitz says. Even adding new sanctuaries won't do the trick. Instead, Rabinowitz says, it's necessary to ensure that jaguars can travel between "dots." That's how a jaguar conservation project called Path of the Jaguar was born.


Rabinowitz's "connect-the-dots" idea came to him after scientists tested jaguars' DNA, or genetic material. They used DNA from jaguar scat, or poop, collected throughout North and South America. They expected to find variations in the DNA that proved jaguars were isolated in their patches of healthy habitat. This would mean that jaguars were evolving into subspecies.

But the scientists got a surprise. The DNA revealed that there are no subspecies of jaguars. The DNA collected from jaguars--from Argentina to Mexico--showed that all the cats were closely related.

According to Rabinowitz, the lack of subspecies proves that somehow the big cats are traveling from dot to dot to find new territory and mates. "They are traveling in corridors that run throughout the human landscape," Rabinowitz says. Getting from one dot to another means jaguars cross cattle ranches, citrus farms, highways, and sometimes even the Panama Canal!

Why would a jaguar set out on such a dangerous voyage? A female jaguar cares for her cubs until they are about 2 years old. After that, she chases them off. Female cubs may settle nearby. But males have to set out on long journeys to find a home range of their own.


For scientists, the surprising DNA test result is good news. It means that the jaguar has a stronger chance of survival as a species.

"All it takes to maintain this genetic mix is one adventurous male in each generation to make it from one dot to the next," Rabinowitz says. He wants to make it easier for these adventurers by protecting the pathways that connect the dots. That means stopping governments from building highways or dams that the jaguars couldn't cross.

"Big cats [like the jaguar] can be saved," Rabinowitz says. For him, the path is clear.

Words to Know

Sanctuary--A natural area where animals are protected from hunters and habitat loss.

Population--A group of the same kind of organisms living in the same environment.

Deforestation--The cutting down of forests.

DNA--A chemical code that carries hereditary information.

Subspecies--A subdivision of a species, on geographic

Counting Cats

How many jaguars are there? Nobody really knows. Counting the cats is difficult because they avoid humans and live in dense forest habitat.

Biologist Santiago Espinosa, a graduate student at the University of Florida in Gainesville, is attempting the first jaguar count in Ecuador. Since the shy cats won't come to him, Espinosa hopes to catch a glimpse with hidden cameras. He has set 26 camera traps in the rain forests.

The cats take their own "self portraits" by tripping heat sensors on the cameras. Each animal boasts a unique spot pattern, so Espinosa can identify individual jaguars from studying the pictures. So far, 16 cats have been caught on film. The cameras have also snapped a variety of prey animals, like white-lipped peccaries and tapir.

Protecting Pathways

Scientists now know that jaguars spread their genes throughout their range. This information has led to new ideas about the best way to keep jaguar populations healthy. Path of the Jaguar's goal is to preserve the routes that jaguars use to travel from one habitat to another.

quick quiz

1. Where is the world's first jaguar sanctuary located?

(A) Mexico

(B) United States

(C) Argentina

(D) Belize

2. What's the goal of the Path of the Jaguar project?

(A) to create more jaguar sanctuaries

(B) to preserve routes jaguars use to travel between habitats

(C) to collect DNA on trails jaguars frequently use

(D) none of the above

3. Which would be another good title for this article?

(A) Animals of South America

(B) Pictures of Jaguars

(C) Safe Travels for Jaguars

(D) Great Cats


* Quick Quiz

(Student Edition, p. 9)

1. d 2. b 3. c



Set a Purpose

Read how a scientist determined that the most effective way to protect jaguars might not be the most expected.


* Jaguars, tigers, leopards, and lions make up a biological group called Panthera. They're commonly called "great cats." Besides their great size, these cats have other differences that set them apart from smaller felines. Only great cats are capable of roaring, and they can purr only while breathing out. Other cats, like house cats, can purr continuously.

* All great cats are either endangered or threatened. Poaching, habitat loss, and loss of prey are their major threats.

Discussion Question

* How might it be important to understand an endangered animal's biology and behavior before you try to save it? (Answers will vary.)


Discussion Question

* Why does Alan Rabinowitz think protecting jaguar migration paths would be more helpful than simply creating more jaguar sanctuaries? (Answers will vary but should include: Studies of jaguar DNA show the animals must travel long distances to breed and spread their genes. To keep jaguar populations healthy they need safe routes to travel from habitat to habitat.)


* For more about threats to jaguars and conservation efforts, visit this World Conservation Society site.

* Visit this site for jaguar facts at a glance.

Wildlife Hot Spots

In "Path of the Jaguar," pages 6 to 9, you read about a region of the Earth that has unique biodiversity. This means that the region has many plants and animals that can't be found anywhere else. Conservationists call places like these biodiversity hot spots. Use the map and graph below to answer the questions.

Major Regions Containing Threatened, Unique Species

1. Which region has the highest number of threatened, unique plants and animals?

(A) Mesoamerica

(B) Tropical Andes

(C) Madagascar

(D) Sundaland

2. True or false: Polynesia/Micronesia and Mesoamerica combined have more threatened wildlife than the Tropical Andes. (A) True

(B) False

3, Which biodiversity hot spot is located entirely north of the equator?

(A) Sundaland

(B) Tropical Andes

(C) Madagascar

(D) Mesoamerica

4. True or false: The Tropical Andes have more than twice as many threatened and unique wildlife species as Madagascar. (A) True

(B) False

5. Which biodiversity hot spot is located southeast of the continent of Africa?

(A) Polynesia/Micronesia

(B) Mesoamerica

(C) Tropical Andes

(D) Madagascar


(Reproducible, T3)

1. b 2. b 3. d 4. a 5. d

Source Citation
Costello, Emily. "Path of the jaguar: some of the world's biggest cats surprise scientists by finding their way through the human landscape.(earth science)(Cover story)." SuperScience Sept. 2009: 6+. Academic OneFile. Web. 1 Nov. 2009. .

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