A prickley pear with cochineal insect
What’s bugging the prickly pears?
Currently some of the prickly pear cacti around New Mexico are
sporting white spitball-like wads among the spines. They hold a
story that begins before the 1500s, a story involving why red is
the color of royalty, how cactus got to the Old World, and the Aztecs’
contribution to red vitamin pills.
Historically, red has been one of the colors most prized by crown,
church and nobility. Kings are often depicted in red robes. When
we wish to treat someone special, we roll out the red carpet. The
reason for this color association is an economic one: prior to the
1500s, the only source of colorfast red dye was a tiny scale insect
that grew on oak trees in Europe. Dye makers had to gather 70,000
of the tiny creatures to produce one ounce of dye. Only royalty
could afford it: Caesar has a full red robe, but his lieutenants
only had red stripes on their robes.
All of this changed with the invasion of Mexico by Cortez in the
early 1500s. When Cortez entered the Valley of Mexico, he was most
impressed by the level of civilization and by the riches he beheld.
He noticed that even the peasants wore red. As the Aztec women washed
the garments in the streams, the color seemed fast. Through the
writings of Cortez’ scribe, we can almost see dollar signs
forming in his eyes.
Cortez found out from the Aztecs that the source of this brilliant
color was small “grains” that occurred in fuzzy white
spots on the prickly pear cactus. When these “grains”
were squashed, they yielded a deep magenta “juice.”
Untreated, this color is not stable in water, but the Indians gathered
the “grains,” fried them on a comal (griddle), added
lime juice, metal ores and other chemicals and produced a permanent
dye called cochineal.
The Aztecs related a legend about two gods who fought bitterly for
the possession of a field of prickly pear. Their blood splattered
on the cactus, giving it the power to pass on to posterity the “blood
of the gods”.
The Spanish began shipping bags of the dye back to Spain. With
cheap Indian labor, the profits were enormous. “Grana cochinilla”
was, after precious metals, the most important Mexican export for
hundreds of years. A reason for the huge profit was that a small
guild of dye makers kept the origin of cochineal a secret for over
300 years. That any secret can be kept for three centuries is amazing.
This one is especially so when one considers the money at stake
and the fact that prickly pear cactus was shipped to Spain early
on so that the industry could proceed there.
Until about 1725, it was believed that cochineal was the seed
of a plant, even though Dr. Martin Lister in 1672 conjectured that
it was some sort of insect, and in 1703 Antony van Leeuwenhoek confirmed
its true insect nature by aid of the microscope. Yet, the news was
slow to disseminate. When explorers from competing European nations
came to Mexico to find the secret of cochineal, they were looking
for seeds instead of insects. Finally, in the 1800s, a spy infiltrated
the dye factory, found that it was bugged, and cochineal became
widely available at reasonable prices.
Prickly pear cactus was brought to Africa and Spain and now looks
so at home that a tourist might assume it was native to the Old
World. Australia also imported cactus for this valuable dye with
disastrous consequences. By 1925, 60 million acres of valuable rangeland
were covered by prickly pear.
Until the early 1900s, cochineal was the main red dye in military
uniforms and clothing, in foodstuffs and in many cosmetics. Michelangelo
painted with it, the British “redcoats” and Canadian
Mounties’ uniforms were dyed with it. Betsy Ross used it for
our first flag. The Navajo, who had no red in their original weavings,
traded in the 1800s for cochineal-dyed flannel blankets (bayetas)
of Spanish soldiers, unraveled them and reused the threads. Then
aniline dyes (from coal tar) and other synthetic dyes were invented
and no one wanted to bother with bugs anymore (except weavers who
always treasure the color). However, when red dye #2 was removed
from the market as a possible carcinogen, there arose a need for
a harmless “organic” red coloring. So cochineal has
made a comeback in cosmetics, fruit juices (ruby red grapefruit
juice), jams and jellies, certain red soda pops, some alcoholic
drinks (Campari), red vitamin coatings, red gelatin desserts, red
candies, and chewing gum. On the list of ingredients, euphemism
such as E120 or the word “carmine” disguises its buggy
origin. The FDA permits cochineal extract and carmine as safe color
additives for food and cosmetics. Despite the “ewwwww”
factor, when one considers the unhealthy alternatives, better this
red than dead.
The insects themselves are fascinating. They are related to aphids,
mealy bugs and scale insects. The tiny winged males live only long
enough to impregnate the females, who are little more than bags
of eggs with a feeding proboscis stuck into the cactus. What one
observes on the cactus (under the white fluff) are the females,
footless and pregnant. They secrete the white, web-like, wax-base
“cocoon” for camouflage and to prevent desiccation.
They also produce a bitter, astringent chemical called carminic
acid that is very effective in repelling potential predators such
as ants. However, since there is no winning the evolutionary arms
race, it is not surprising that one predator has gotten past the
defense. A caterpillar of one moth species eats cochineal insects
and stores the bitter chemical in its gut to be used later against
the ants that are its natural enemies.
Reprinted with permission from Share with Wildlife
(Summer, 2005), a publication dedicated to the conservation of all
New Mexico wildlife.