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The “grotesque” baobab tree has long been known as the “tree of life” for its ability to create and maintain its own ecosystem in arid regions. Since the time of the ancient Egyptians, people have marveled at what researchers say are among the “most charismatic species on our planet,” but no one knew where they came from—until now.

There are currently eight species of the tall and broad-stemmed plants, also known as upside-down trees or the “mother of the forest”. Of these groups, six species occur in Madagascar, one occurs in continental Africa, and another occurs only in northwestern Australia.

But only one of these places is the true origin of them all.

Researchers claim to have solved the mystery of the ‘spectacular trees’ using the species’ DNA. In a new study published in Nature, they said all the trees came from the African island nation of Madagascar.

Baobabs have “fascinated botanists, tourists, naturalists and passers-by for centuries,” the study said. “Probably the earliest record of people marveling at these amazing trees can be traced back to the ancient Egyptians, around 2300 BC. With their grotesque appearance, enormous size, renowned longevity and diverse uses, Baobabs have become one of the most charismatic species on our planet.”

It was hard to pin down that charisma. But researchers say that after picking leaves from the species and analyzing genomes, they were able to determine that their common ancestor was based in Madagascar. Over time, members of the species were radiated off the island, creating hybrid species that would evolve to have different flowers that attracted different other animals.

“We were delighted to be involved in this project revealing patterns of baobab speciation in Madagascar followed by the astonishing long-distance dispersal of two species, one in Africa and one in Australia,” said Andrew Leitch, professor at Queen Mary University of London “. “This was accompanied by the evolution of some fascinating pollination syndromes involving hawkmoths, lemurs and bats.”

According to the San Diego Zoo Wildlife Alliance, baobabs are “like no other.”

“A thick, bottle-like trunk rises to support slender branches. Baobabs are deciduous and during the dry season (which can last up to nine months) the bare branches of the baobab resemble a gnarled root system and make these trees look as if they have been uprooted and pushed back upside down,” the organization said .

The alliance says trees not only play a key role in their ecosystems, but create their own. In addition to helping the soil stay moist, recycling nutrients and preventing erosion, they also provide food, water and shelter to other species.

The smallest species of baobab grows up to 16 feet, while the largest of the trees can grow to about 82 feet in height, with a girth that measures the same or even more. By comparison, a semi truck is usually about 72 feet long.

But many of these trees face a conservation battle. All but one of the species are on the IUCN Red List of Threatened Species, with three considered endangered, one considered critically endangered and one considered endangered, the study said. Only one species is classified as “Least Threatened”, although its populations are declining.

The DNA results show that some of the trees have low genetic diversity, a key component for species survival as it helps establish resistance to environmental changes. Their findings also suggest that climate change “will pose a serious threat” to one of the species living in Madagascar and could force it to disappear before 2080. Based on this, the researchers say their findings should cause reassessment of the conservation status of baobabs.

The San Diego Zoo’s Wildlife Alliance also noted a “rapid increase” in tree deaths in South Africa.

“Of the 13 largest baobabs on the continent, 9 have collapsed and died,” the group said. “The cause is unclear, but scientists suspect that global climate change may be playing a role in the demise of these trees.”