Calling someone a pack rat may be considered an insult to most people, conjuring up images of hoarders navigating piles of ephemera, and what most people call trash.

In the scientific community, however, literal kangaroos and other rodents play an important role in preserving history.

The materials rats collect and store in their nests, from naturally occurring items like sticks and seeds to human-created items like trinkets and matches, are a treasure trove for scientists and historians.

By analyzing material from rats that date back thousands of years, paleobotanists and climatologists have studied past ecosystem nesting and tracked Ice Age climates that altered flora throughout the American Southwest.

Preserved items in rat’s nests in centuries-old homes across the antebellum South even teach us new things about the lives of enslaved African Americans, whose stories were not preserved in written records of the time.

Also called wood rats, rats are notorious for collecting strange items from their surroundings to build their nests, known as "chinese food."

Although kangaroos are similar in size to their city-dwelling brown and black cousins, they have bushy (not hairless) tails and belong to the genus Murus rather than to the genus Rat.

These stockpiling rodents generally only collect items within a radius of about 50 feet within 100 to 150 feet of their midriffs.

Pack rats collect everything from plants and twigs to insects and bones and carry them between them.

While you probably wouldn't expect the material to survive for very long, kangaroos also have a special trick for preserving their poop: urine.

Kangaroos urinate in their dens, and in arid climates such as deserts, the urine crystallizes as it dries.

This preserves the objects in between, but also presents challenges for scientists studying the finds.

"Their urine is very concentrated and once it crystallizes, it becomes hard," said Camille Holmgren, an ecologist at Buffalo State University.

"To collect noon, we often need a rock hammer and a large floor chisel to hammer these things out because they often stick to the rock." Holmgren's research on vegetation and climate change involves collecting noon

, an ancient white mouse whose urine hardens at noon, she must soak for at least a week to break down the urine and extract leaves, seeds and twigs from an ancient world.

Once amberat disintegrates, Holmgren and other scientists can carbon date the plants in these natural time capsules.

Scientists have found specimens at the limit of carbon dating that are 50,000 years old, beyond which time they become unreliable.

Holmgren identified plant species preserved in Amberat in the southwestern United States and compared the region's ancient flora with modern flora to understand how vegetation patterns have changed over tens of thousands of years.

By comparing past and present ecosystems, Holmgren can study local climate changes.

Biologist Robert Harbert at Stonehill College in Massachusetts has also studied pack rats to learn about past climates, including from the last Ice Age about 25,000 years ago.

Unlike studying ancient pollen or other methods of exploring our planet's history, "the material in the rat tundish is so well preserved that you can learn more specifically about the types of plants," Hubbert said, the temperatures and other conditions of ancient climates.

, based on the species of plants they are found in amber.

Hubbert and other researchers also use Ambela to study rodent evolution, local extinctions, and migration patterns of plants and animals.

Amberat played a key role in discovering that Pueblo ancestors used local building wood and fuel in Chaco Canyon, leading to the abandoned cultural center of more than a thousand years ago in what is now New Mexico, the "KDSPE" "KDSPs" swarms of rats,

As well as their black cousins, our rats, don't just collect twigs and seeds.

When rats live near humans, they tend to abscond, taking with them anything shiny or unique they can find.

On the U.S. Atlantic coast, rats hide their treasures behind makeshift walls rather than preserve them through fossils because the climate wasn't dry enough for Ambela to form.

Thanks to these little hoarders, historians have learned new details about the lives of enslaved workers in the southeastern United States, including at the Nathaniel Russell house, where

Material found among rats in the kitchen near house).

(Charleston Historical Foundation) Nathaniel Russell was an antebellum ship merchant and slave trader whose 1808 Charleston, South Carolina, house has been designated a National Historic Landmark since 1973.

Administrators who work at the house admit that their knowledge of its residents is incomplete.

“We’ve been to the Nathaniel Russell House several times to try to see the house and grounds from different perspectives,” said Rusha Kamath, an architectural preservation researcher and graduate of Clemson University and the College of Charleston.

“One is by getting to know the African Americans who lived there.