Before agriculture became industrialized, there was a much greater diversity of plants being grown for food.
For instance, there are more than 4,000 different varieties of potatoes, but in the United States, only about five to eight varieties are widely used.
From artificial selection, to monocultures for mass production, to genetic modification, the industrialization of agriculture – and the supply chains that distribute these products – has whittled away the variety of vegetables that wind up on our tables.
A review by the United Nations' Food and Agriculture Organization (FAO) estimates that 24 percent of the wild relatives of vegetables assessed at the species level are at risk of extinction.
And as we lose the genetic diversity of vegetables, we also lose their nutrients and the ability to adapt our crops to changing climate conditions.
"A few species, such as lettuce, onions, and tomatoes, have become global crops and are part of diets worldwide," van Zonneveld and team write.
"Many others, such as spider plant, slippery cabbage, and bitter gourd, which are typically denser in micronutrients and better adapted to challenging and resource-limited environmental conditions, are available only regionally, and very often neglected in large-scale food policies and strategies."
https://www.sciencealert.com/the-worlds-vegetables-are-vanishing-and-its-quietly-wrecking-our-diets
"Currently, only a few local varieties are conserved in gene banks, with many gaps in collections, constraining breeding and the development of improved varieties for larger-scale production," van Zonneveld and team note.
Slippery cabbage is one of the most popular dark-green leafy vegetables in the Pacific, where the researchers say it has potential to greatly improve women's and children's nutrition especially.
Bitter gourd is another climate-resilient vegetable popular in Asia and the Caribbean that has many wild relatives, which the researchers think could improve crops in these tropical regions.
And then, there's the well-known pumpkin, which can tolerate drought and heat, while producing fruits rich in beta-carotene. Despite its commercial importance, the researchers say "its genetic resources remain underutilized and poorly conserved".
The researchers think these four vegetables could be great starting points for diversifying food crops regionally, but there's plenty of others.
We just need to start growing and eating them, before they disappear.
Related: Scientists Found a Remarkable Way to Help Kids Like Vegetables
"The ongoing biodiversity loss for these and the other 1,480-plus vegetable species occurs at a time when global food systems urgently need diversification," the team concludes.
"Alignment under a global initiative would ensure that local and regional efforts translate into improvements in diets at both the local and global levels."
Closer to home, we can add more diversity to our diets in a few ways.
If you're a keen gardener, look for 'landrace' and 'heirloom' varieties of vegetables to grow in your garden.
Collecting seeds from your own vegetables to grow again next year is another great way to keep that biodiversity rolling – you might even end up with your own unique varieties.
Shopping for groceries at farmers' markets and independent grocers is also a great way to find a wider range of vegetables (and fruits) to add to your diet.
Who knows, you might even find a new favorite.