Curio Cabinet

We might need to redefine what qualifies as hardwood! Fig trees are known for their delicious fruit, but they may soon be useful as a means of carbon sequestration after scientists discovered that they can turn themselves into stone. It’s not exactly news that trees, like all living things, are made out of carbon. Compared to most organisms, though, trees are great at sequestering carbon. They turn carbon dioxide into organic carbon, which they then use to form everything from roots to leaves. Since trees live so long, they can store that carbon for a long time. That’s why, to combat climate change, it’s a good idea to plant as many trees as possible. It’s a win-win, since trees can also provide food and lumber to people and form habitats for other organisms. One tree, however, seems to be a little ahead of the curve. The Ficus wakefieldii is a species of fig tree native to Kenya, and scientists have found that it can turn carbon dioxide into calcium carbonate, which happens to be what makes up much of limestone. Apparently, other fig trees can do this to some extent, but F. wakefieldii was the best at it out of the three species studied.
 
The process is fairly simple. First, the trees convert carbon dioxide into carbon oxalate crystals, and when parts of the tree begin to naturally decay from age, bacteria and fungi convert the crystals into calcium carbonate. Much of the calcium carbonate is released into the surrounding soil, making it less acidic for the tree, but much of it is also stored in the tissue of the tree itself. In fact, scientists found that in some specimens, their roots were completely converted to calcium carbonate. Surprisingly, F. wakefieldii isn’t the only tree capable of doing this. The iroko tree (Milicia excelsa), also native to Africa, can do the same thing, though it’s only used for lumber. Fig trees,on the other hand, can produce food. Either way, carbon minerals can stay sequestered for much longer than organic carbon, so both species could one day be cultivated for that purpose. The real question is, if you wanted to make something from these trees’ wood, would you call a carpenter or a mason?

 
[Image description: A brown, slightly-split fig on a bonsai fig tree.] Credit & copyright: Tangopaso, Wikimedia Commons.

These mountains look cool, but they can be real hotheads. Researchers from the University of Wisconsin–Madison have presented a study at the Goldschmidt Conference in Prague suggesting that dormant volcanoes around the world may become more active as a result of melting glaciers. First, some clarification: there are three main volcano classifications depending on their level of activity. “Active” means that the volcano has erupted during the Holocene epoch (the last 11,650 years or so) and has the potential to erupt again in the future. “Extinct” means that, as far as anyone can tell, the volcano is unlikely to ever erupt again (though it happens from time to time). “Dormant”, on the other hand, means “potentially active,” as in, it’s an active volcano (the first classification) that’s just not erupting presently, as opposed to “actively erupting,” which means magma is currently coming out of the ground.
 
A lot of factors contribute to a volcano’s dormancy, and scientists have found that glaciers are one of them. Researchers tracked volcanic activity by measuring the radioactive decay of argon in crystals formed in magmatic rock. They then compared that to the level of ice cover during the peak of the last ice age. What the data seems to suggest is that the ice cover acted as a lid, inhibiting eruptions. As the ice melted, volcanoes became more active. Currently, there are an estimated 245 dormant volcanoes buried under three miles of ice, and many of them are in Antarctica. Once these begin to erupt due to the reduction in ice cover, it may create a feedback loop as the eruptions themselves further melt the ice. It seems there will be an icy reception before things really heat up.

 
[Image description: A portion of the Andes mountain range between Chile and Argentina, photographed from far above.] Credit & copyright: Jorge Morales Piderit, Wikimedia Commons. The copyright holder of this work has released it into the public domain. This applies worldwide.
 

These critters are as American as apple pie, but a whole lot bigger! North American bison, also called buffalo, are the largest land animals in North America and some of the most historically significant. Yet, we almost lost them altogether. Overhunted throughout the 19th century, there were fewer than 600 bison left in the U.S. by 1889. Today, their numbers have recovered drastically, but these gentle giants still have a long way to go.
 
There are two species of bison: The North American bison and the European bison. North American bison are often called buffalo, but they aren’t actually buffalo at all. Real buffalo, like cape buffalo and anoa, live in Africa and Asia. However, bison are closely related to buffalo and share many traits with them, since they’re all bovines—members of the family Bovidae’s subfamily, Bovinae. As such, they share many attributes with buffalo, including their large size, horns, and hooves, as well as behavioral traits like living in herds. Bison are famous for their fluffy winter coats, which help them survive harsh, blizzardy winters in places like the Northern Great Plains. That’s not to say that bison are sweet and cuddly, though. They are massive, powerful animals; males can stand up to six feet tall and weigh up to 2,000 pounds. Like any wild animal, they can become aggressive if approached, especially during mating and calving season. It’s a fact that tourists sometimes learn the hard way when they don’t obey rules in places like Yellowstone National Park, where the largest bison population in North America roams free.
 
Bison first appeared in North America during the late Middle Pleistocene epoch, between 195,000 and 135,000 years ago. Before European colonists began settling in North America en masse in the late 15th century, there were around 30 million bison roaming in what is now the United States. Many native tribes relied on bison meat and hides, with some, like the Plains Indians, focusing many parts of their lives around the movements of bison herds. However, as colonist aggression toward native tribes increased and native peoples lost control of more and more land, the bison population dwindled. During the American Indian Wars of the 17th, 18th, and early 19th centuries, bison were deliberately killed by colonists as a means of harming native peoples and to feed colonial soldiers. By the 1880s, there were as few as 300 bison left in what is now the United States. The species was on the brink of extinction.
 
Luckily, private organizations and ranchers stepped in to save North American buffalo, keeping herds on private land where they couldn’t be hunted. In 1902, 21 bison from private owners were placed in a designated area at Yellowstone National Park. Eventually, they were reintroduced to the wild, and began breeding with Yellowstone’s existing wild population. In 1905, the American Bison Society started a bison breeding program that also helped spread awareness about the importance of wild bison. Theodore Roosevelt aligned himself closely with the organization and even served as its honorary president for a time. Today, thanks to over a century of conservation efforts, there are roughly 31,000 wild bison in the United States. It’s a far cry from the millions that once roamed here, but it’s a whole lot better than extinction, and that’s no bison hockey!

 
[Image description: An adult and baby bison standing on a shrubby plain.] Credit & copyright: Anna Weyers Blades/USFWS. Public Domain.