Actor Roseanne Barr at Walt Disney Studios in Burbank, Calif., on March 23, 2018.  (Valerie Macon/AFP/Getty Images)

Comedian and former ABC sitcom star Roseanne Barr became the latest social media casualty when the network canceled her show “Roseanne” after a tweet about Valerie Jarrett, who was a senior adviser to President Barack Obama, in which Barr compared Jarrett to a blend of the Muslim Brotherhood and the film “Planet of the Apes.” Nor was it the first time Barr referred to a black woman using the ape trope — in 2013, she wrote a similar tweet about Obama’s national security adviser Susan E. Rice. As president and first lady, Barack and Michelle Obama were subject to similar insults.

While Barr and others dismiss their association of people of African descent and apes as a mere joke, this racist trope has been used for centuries to condone slavery, segregation, even eugenics. The trope has its roots in 16th- and 17th-century European and American thought, when it was used to argue that Africans were subhuman, thereby justifying the enslavement and second-class citizen status of African peoples.

The dehumanization of African peoples is rooted in what scholar Anne McClintock has dubbed “the porno-tropic tradition.” For centuries, Europeans saw Africa as a site of sexual vice. European lore abounded with tales of the “monstrous sexuality of far-off lands where, as legend had it, men sported gigantic penises and women consorted with apes.” From the second century on, such figures as Ptolemy, Leo Africanus, Francis Bacon, John Ogilby and Edward Long envisioned the inhabitants of Africa as the most sexually promiscuous beings to inhabit the earth.

Englishmen began incursions into West Africa in the mid-16th century. These first explorers were informed by literary myths like those from the medieval era, which portrayed bestiaries of strange creatures who resembled humans. In 1607, for instance, “The Historie of Foure-Footed Beastes” by Edward Topsell explicitly described the lustful disposition of apes, connecting them to devils, associations that would become common in England. The English began propagating their own myths based on supposed correlations between Africans and tailless apes called orang-outang. As historian Winthrop Jordan contended, characterizations about apes “revolved around evil and sexual sin; and rather tenuously connected apes with blackness.”

While some 17th-century commentators suggested Africans were descended from apes or that apes were descended from “blacks and some unknown African beast,” the notion that apes were fond of African women and inclined to rape them became widespread. Eighteenth-century Enlightenment thinkers such as John Atkins lent credence to these ideas, writing that “the Negroes have been suspected of Bestiality with them, apes and monkeys, and by the Boldness and Affection they are known under some circumstances to express to our females.”

These racist ideas were not limited to England. In “Notes on the State of Virginia,” Thomas Jefferson argued that black men were a “lower species” lusting after white women. He expressed hyper anxiety about interracial relationships — though he would later have children with Sally Hemings, an enslaved woman — by equating sexual desire with a preference to maintain one’s superior race traits (that is, their whiteness).

“Are not the fine mixture of red (blushing) and white the expression of every passion by greater or less suffussions of colour in the one, preferable to that eternal monotony . . . the immoveable veil of black which covers all the emotions of the other race?” Jefferson wrote. He then invoked the timeworn myth of black women engaging in bestial relations, arguing, “Their own judgment in favor of the whites, declared by preferences of them, as uniformly as is preference of the Oranootan for the black woman over his own species.”

In other words, he believed black men were filled with lust for the superiority of the white female body as a means to elevate themselves, just as an orangutan lusted after the bodies of black women to elevate itself. In both scenarios, black people were viewed as subhuman and inferior to whites.

By the 19th century, the racist notion of blackness as bestial was burned into the European and American psyche, justifying the centuries-long enslavement of African peoples who were chained and herded like cattle onto slave ships to be sold at auction to the highest bidder. Reduced from human beings  to chattel, slaves endured speculators prodding and picking at their potential commodity to ensure the quality and production in labor. For women, their childbearing potential as “breeders” to reproduce the slave labor force was seen as a premium. The inspection included the public examination of teeth, limbs and private parts. Such indiscretion was viewed as natural because of their status as property rather than people.

Blacks were characterized as brutes who needed to be under the authority of whites so as to keep their bestial nature in check. Free blacks were always viewed as a threat to white society, an anxiety heightened during the post-Civil War era as white fears of a nation of newly freed slaves gave rise to the theory of retrogression, which contended that freedom would cause blacks to revert to their lowest type, unleashing crime and violence, particularly black male sexual violence against white women.

These sentiments underscored Jim Crow segregation, a doctrine of separate and unequal, a legacy that continues to haunt the nation.

The racist ideology of the ape trope is no joke. It has had devastating effects on black people globally. Its continued use reinforces notions of blacks as inferior, subhuman and bestial, which in turn continues to justify their subjection and quasi-citizenship both nationally and globally. As Jarrett stated on “Everyday Racism in America,” a town hall hosted on Tuesday by MSNBC: “I see this as a teaching moment. I am fine. I worry about those people without friends and followers who come right to their defense,” and “those ordinary examples of racism that happen every single day.”

If we are to become a society where black lives, rather than race, matters, these teaching moments must also become learning moments.

Correction: An earlier version of this report incorrectly referred to Francis Bacon Hermit. The correct name is Francis Bacon.