Their suggestive appearance make figs and asparagus perennially popular with ‘top ten’ aphrodisiac foods lists, while chocolate and oysters can lay claim to more substantive amatory charms. But all four are under threat from climate change, which could eventually price some off Valentine’s Day dinner shopping lists for all but the most affluent of admirers.
Forget heart-shaped boxes and squared-off samplers. The Aztec king Montezuma II demanded his 50 daily servings of chocolate be delivered in solid-gold pitchers, which, according to legend, were used just once and then tossed in a lake. Unfortunately for the more plebian addicts among us, chocolate may again become a precious and rarified food, thanks to climate change-induced warming along with steadily growing demand.
Grown within 10 degrees of latitude on either side of the equator, what cacao plants desire most is constancy. But predicted rising temperatures and falling precipitation levels would render inhospitable much of the current cacao regions in Africa’s Ghana and Cote d’Ivoire, according to a 2011 study by the International Center for Tropical Agriculture (CIAT).
Meanwhile, supply is dwindling for other reasons. There is a growing consumer preference for antioxidant-rich dark chocolate, which requires as much as three times more cacao inputs than the more dilute milk chocolate. And there are also more devotees than ever, with emerging middle class consumers in China and India clamoring for a taste.
If demand keeps rising while supply is disrupted, that Valentine’s Day box of chocolates could move from the realm of welcome-but-cliché gift to jewelry-level significant.
Bisect a fig lengthwise, and it is immediately obvious why figs perennially populate “top ten” lists of aphrodisiac foods, inspiring the likes of D.H. Lawrence to write “Figs,” a poem with 81 lines, including this one: “Like a prostitute, the bursten fig, making a show of her secret.”
In fact, many scholars believe it was a fig, not an apple tree that bore Adam and Eve’s forbidden snack, both because the garden would have been in subtropical Palestine and because it was fig leaves, after all, that the newly self-conscious couple grabbed in their mad scramble for cover.
At first blush, these sensual fruits would seem more well-positioned than most to adapt to climate change. They have abundant genetic diversity, with more than 700 species in the wild available for hybridizing. Unfortunately, figs have a little little ‘birds and bees’ problem. They’re locked in a co-dependent relationship with a much more climate-vulnerable partner: the fig wasp.
Fantastically, most fig species have a unique “obligate” fig wasp species that services them during the tiny insect’s one-to-two day lifespan. But that monogamy could prove to be both species’ undoing.
Female fig wasps carry pollen and lay eggs inside what is technically an inverted male flower; its reproductive organs cradled inside. Riddled with obliging chambers, the male fruit serves as a nursery for the baby fig wasps while the female fruit, the one we eat, spreads its seed. But this millennia-long “friends with benefits” arrangement is threatened by climate change driven warming.
A 2013 study published in the journal Biology Letters found that the warmer conditions get, the shorter these wasps’ lifespans grow – dwindling to as few as six hours according to researchers at the National University of Singapore. That might be enough time to get the reproductive deed done if the fig wasp could flit promiscuously from flower to flower. But fig pollination takes time and commitment. To get inside, the female fig wasp must wriggle through a tunnel so narrow that her wings and antennae will get knocked off along the way. Continued warming in the tropics, the researchers write, could eventually lead both lovers to their deaths, “destabilizing the mutualism in the short-run and possibly leading to co-extinctions in the long-run.”
While asparagus and figs are deemed aphrodisiacs by dint of their suggestive appearance, oysters have both style and substance.
Two rare amino acids found in these bivalve mollusks led to increased testosterone production in male rats and progesterone production in female rats, scientists reported in 2005.
Slurping them raw (legendary lover Casanova reported ate 50 raw oysters before embarking on his amorous adventures) and in the springtime offers the highest levels of D-aspartic acid (D-Asp) and N-methyl-D-aspartate (NMDA), according to the report.
Unfortunately, oysters are under assault – from climate change driven ocean acidification that’s hammering coral reefs, to diseases that scientists say have been exacerbated by warming oceans.
Scientists say ocean acidification is the culprit that has been killing oyster seedlings by the billions in the West Coast’s most prolific and valuable fisheries. Briefly, some 30 percent of the carbon dioxide humans have emitted since the Industrial Revolution has sunk into the oceans rather than the atmosphere, which, until relatively recently had been lauded as a positive. But chemical reactions driven by all that CO2 have made oceans approximately 30 percent more acidic than before humans began burning fossil fuels in earnest and in the process made certain compounds and building blocks less available to marine life. Oregon and Washington oyster farmers have begun bathing their developing oysters with carbon-rich solutions, including calcium carbonate, to help seedlings survive. So far, only certain regions where ocean currents cause “upwelling” of colder – and therefore more CO2 laden water – are affected. But the problem is growing, and sooner than predicted, with oceans acidifying faster than they have in 20 million years, according to a September report from the U.S. Government Accountability Office. Without changes, scientists say the oceans will be 150 more acidic than in pre-industrial times by the end of this century.
The phallic shape of its spears seems to be the primary reason this springtime vegetable makes the aphrodisiac list. (19th Century bridegrooms in France reportedly feasted on it in the days leading up to their nuptials, as it was thought to ensure connubial success on the big night.)
But now, it seems, the guilty pleasure of having asparagus flown 3500 air miles from Peru
to grocery stores in the US (6000 for asparagus-lovers in the UK) may be coming home to roost, as climate change induced warming now threatens the already unsustainable practice of growing the vegetable in monoculture in one of the driest places on earth.
With the exception of China, Peru grows more asparagus than any other country, much of it in the Ica Valley in the middle of the Andean desert. While asparagus production provides jobs and income for a very poor area, it has done so by driving tremendous water deficits that are expected to get worse as climate change driven warming shrinks the glaciers that feed the area’s water basin. Meanwhile, supply from Mexico, the U.S.’s principal asparagus import source, is expected to be down 50 percent this year and California, the US’s largest supplier, is locked in a once-in-1200-years drought, imperiling the supplier of half of the country’s fruit and vegetables.
There’s no romanticizing the effects that unfettered climate change could soon bring upon our food systems, whether they be aphrodisiac or merely sustaining. What’s urgently needed is for Earth-lovers everywhere to ardently press their suit for change.