specimens

Almost a dire wolf

April 22, 2025 By EarthWise Leave a Comment

Researchers around the world are working on what some call the ‘de-extinction’ of iconic animals of the past such as the wooly mammoth, the dodo, and the Tasmanian tiger. The idea is to decipher the genome from DNA of preserved specimens and, using the tools of modern genetic engineering and cloning technology, alter the DNA of closely related modern species to recreate the extinct species.

A company called Colossal Biosciences recently announced that it has brought back the dire wolf, a species that has been extinct for 10,000 years. Dire wolves have white coats and are larger than modern wolves, have more powerful shoulders, a wider head, and larger teeth and jaws. Colossal is now raising three wolves they have engineered at a 2,000-acre site at an undisclosed location.

The wolves were created by taking the DNA of modern grey wolves and editing 14 genes substituting ones from ancient dire wolf specimens. Wolves have about 19,000 genes, so the changes from the grey wolf genome are very minor but enough to produce an animal that looks just like a dire wolf. But is it a dire wolf?

It really isn’t. Ancient DNA is always greatly damaged. Only parts of it survive. We don’t actually have the complete genome of the dire wolf. What we have is bits and pieces that, thanks to modern technology, allow us to produce a phenotype of a dire wolf; that is, an animal with the same observable features.

Whether this accomplishment is a worthwhile and appropriate thing to do is a question that continues to be debated.

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The Return of the Dire Wolf

Photo courtesy of Colossal Laboratories & Biosciences.

Earth Wise is a production of WAMC Northeast Public Radio

Is de-extinction possible?

January 28, 2025 By EarthWise Leave a Comment

Advances in genomics have created the possibility of bringing back extinct species from the past by making use of recovered DNA from preserved specimens. Companies attempting to “de-extinct” iconic species have received hundreds of millions of dollars from venture capitalists.

These companies are trying to bring back iconic species that include ivory-billed woodpeckers, Tasmanian tigers, dodos, passenger pigeons, and woolly mammoths.

Efforts to recreate extinct species are controversial. The arguments in favor include the positive effects on ecosystems when keystone species are restored, and the excitement generated about conservation in general. The opposing view is that concentrating all this effort on these restorations diverts attention and funding from more urgent conservation work.

A more nuanced viewpoint that has emerged is that actually de-extincting species is not possible. The genome of these vanished species cannot be reconstructed perfectly. Specimens are not cryopreserved from when the animal died. What can be retrieved is at best significant fragments of the genome. These are combined with DNA from related contemporary animals to produce the new species.

As a result, what emerges are proxies. They are animals that are similar to extinct animals – in some cases convincingly so – but they are not the same species that existed in the past. They may be able to fill the same ecological niches and they may have similar behavior. But they are not de-extincted specimens of the past species. Is it worth doing? Quite possibly but it’s not actually bringing back what is gone.

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Despite Biotech Efforts to Revive Species, Extinction Is Still Forever

Photo courtesy of Grazelands Rewilding.

Earth Wise is a production of WAMC Northeast Public Radio

A dangerous invasive species

August 28, 2024 By EarthWise Leave a Comment

Weeds are the bane of every gardener’s existence. They pop up, uncontrolled and unwelcome, and must be tediously managed time and time again. But in some cases, weeds are more than just a nuisance. Some are a public health hazard.

Meet giant hogweed. Native to Europe’s Caucasus Mountains, giant hogweed belongs to the carrot family. The plant resembles Queen Anne’s Lace – on steroids. Giant hogweed can grow up to 15 feet tall with three inch stems, five-foot-wide leaves, and an umbrella-like canopy of white flowers.

Botanists brought giant hogweed to England as an ornamental plant in the 1890s. It made its way to the U.S. via horticultural channels. In fact, one of the first specimens was planted in a Victorian garden near Rochester, NY.

As with most invasive plants, it quietly escaped cultivation. In the U.S., giant hogweed can be found in New England, the Mid-Atlantic Region, and the Northwest, with plants preferring moist habitat near roadside ditches and stream banks.

While a seemingly innocent flowering plant, giant hogweed is actually one of the most hazardous plants in the U.S. Brushing against or breaking the plant releases sap that, when combined with sunlight and moisture, can cause severe burn-like lesions, blistering sores, and purplish or blackened scars. Getting sap in your eyes can result in temporary or even permanent blindness.

With each plant dropping up to 120,000 seeds, it’s no surprise that giant hogweed is proving difficult to eradicate.

If you suspect giant hogweed is growing near you, photograph the plant from a safe distance and report the sighting to local environmental authorities.

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Plant Pest Risk Assessment for Giant Hogweed

Giant Hogweed

Photo, posted March 22, 2021, courtesy of Scottish Invasive Species Initiative via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Ivory-Billed Woodpecker | Earth Wise

May 24, 2022 By EarthWise Leave a Comment

The ivory-billed woodpecker was the largest woodpecker in the US. They were once relatively common, stretching from the Carolinas through the southeast and across to Texas. Their numbers started to drop sharply in the 19th century because of habitat loss and overhunting. Many were taken as valuable specimens; some were even eaten by poverty-stricken people.

The last widely accepted sighting was way back in 1944. For years, the birds were listed as critically endangered with only infrequent and entirely anecdotal reports of sightings. Last year, the U.S. Fish and Wildlife Service finally declared the species extinct.

A multiyear field study by avian researchers from multiple institutions has recently reported that the ivory-billed woodpecker may in fact still exist in a remote swampy region of Louisiana.

The three-year effort to find the woodpecker involved scientists trudging through the remote site to observe birds and take audio recordings. Unmanned trail cameras taking time-lapse photos and a drone were used to capture images. Several members of the team report that they observed the birds. Some photographic images and videos appear to show ivory bills. Based on characteristic markings visible in some of the photos, the birds do appear to be the ivory bill and not, for example, the fairly common but similar looking pileated woodpecker.

The birds are scarce, live in a tough, swampy habitat, and actively avoid getting near people. They live high in trees and are very difficult to spot, much less get clear photographs of. From all indications, however, reports of the demise of the ivory-billed woodpecker may have been premature.

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Back from the dead? Elusive ivory-billed woodpecker not extinct, researchers say

Photo, posted May 3, 2008, courtesy of Michael McCarthy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving The Giant Sequoia | Earth Wise

April 22, 2021 By EarthWise Leave a Comment

Giant sequoia trees are some of the most remarkable living things on earth. They can live up to 3,000 years. The tallest specimens tower over 300 feet, but it is their girth that really sets them apart. They are usually 20 feet in diameter, and some are up to 35 feet across at the widest. The largest tree in the world by volume is the General Sherman tree, which has a volume of 52,508 cubic feet. At 2,100 years old, it weighs 2.7 million pounds and is not only the largest living tree, but also the largest living organism by volume on the planet.

Giant sequoias are incredibly hardy. To have survived thousands of years, the oldest of these trees have endured hungry animals, diseases, fires, snowstorms, El Niño events, years-long droughts, and the efforts of loggers during the 19th and 20th centuries.

In February, unusually high winds knocked down 15 giant sequoias in Yosemite National Park. While sequoias are amazingly adapted to their narrow range in California’s Western Sierras, it appears as though climate change is altering their habitat faster than the species can migrate or adapt. Shorter cold seasons have meant more rain instead of snow, leading to floods and mudslides in the winter. Fires are more likely with less snowpack. Hotter, drier summers put sequoias under greater stress.

Forest managers work to preserve existing groves through fire mitigation, supplementary water, and careful stewardship of young trees in existing groves. If these efforts are successful through the ensuing decades, climate change may be just one more thing the sequoias outlasted. But at least some conservationists are now considering planting a new generation of sequoias in colder, nearby habitats.

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To Save Giant Sequoia Trees, Maybe It’s Time to Plant Backups

Photo, posted June 8, 2008, courtesy of Joi Ito via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.