Tag Archives: cats


Republished by Blog Post Promoter

ichneumonidae__phrudinae“I own that I cannot see as plainly as others do, and as I should wish to do, evidence of design and beneficence on all sides of us. There seems to me too much misery in the world. I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of Caterpillars, or that a cat should play with mice.”

~  Charles Darwin, letter to Asa Gray, May 22, 1860


Female_Ichneumon_xanthoriusIchneumonidae is a family of parasitic wasps, and one of my particular research interests.  If you’ve never heard of a parasitic wasp before, think chest-burster from Alien, but for insects. A more scientific definition is that parasitoid wasps lay their eggs inside or on top of other insects; those eggs then grow and develop by feeding on their host’s tissue, resulting in the eventual death of the host.  Estimates of the total species range from 60,000 to over 100,000.


The decree that “cats are evil” by the catholic church created the conditions that lead up to THE BLACK DEATH by associating the common house cat with Satan. The Black Death is estimated to have killed 30% to 60% of Europe’s population, reducing the world’s population from about 450 million to between 350 and 375 million around 1400.

Remember that the plague was spread by fleas that lived on rats. A viscous cycle kept the disease going. Infected fleas would bite a rat, and the rodent would become infected. Then other fleas biting the infected rat would become infected themselves. Once the host rat died of the plague, any fleas living on it would find themselves homeless and would go in search of a new host. Unfortunately, this often took the form of a human. When the sick infected fleas bit the human in order to feed, the human would become infected. So why didn’t the Europeans just keep plenty of cats around to kill the rats and thereby reduce the incidence of the plague? They had cats at the time. They were originally brought to Europe by the Romans, who had discovered the felines in Egypt. Keeping pet cats as mousers had become popular in Europe by the time of the first plague.

The black plague, also known as the Black Death, is a disease caused by the bacterium Yersinia pestis. It enters the body through the skin and travels via the lymph system. The bacteria live in the digestive tracts of fleas. The fleas, of course, live off blood from a host, and when the fleas swallow the blood, it becomes infected with the bacteria. As the bacteria multiply inside the flea, an intestinal blockage forms, starving the parasite because nutrients cannot be absorbed. The flea vomits in an effort to clear the blockage, and since the flea is starving, it feeds voraciously. When the infected flea vomits the diseased blood into a bite site on a host animal or human, the host becomes infected with black plague.

The disease was once devastating, and the resulting death was horrible. There were actually three forms of the black plague – the bubonic form, the pneumonic form, and the septicemic form. Victims of the bubonic plague suffered painful swollen lymph nodes in the neck and the underarms, called buboes. They were also wracked with high fever, vomiting, pounding headaches, and gangrene. Some were so weak that they barely had the energy to swallow.

The pneumonic form was even more punishing. As the body tried to fight off the disease, large amounts of phlegm were produced. The victims had to constantly cough up sputum in an effort to breathe, and more than ninety-five percent of the time, the patient drowned in his own body fluids. The pneumonic form of the plague didn’t need rats or fleas to spread – it was an airborne bacterium spread by the coughs of infected individuals.

Septicemic black plague was a form of blood poisoning and had a mortality rate of one hundred percent. With this type of plague, the individual suffered from high fever and purple blotches on the skin. Fortunately, this deadliest form was also the rarest.

From the middle of the 1300s until the 1700s, the black plague terrorized much of Europe and parts of Asia. Most historians believe the plague was first brought to Europe on ships from Asia. The most likely culprit was the black rats that often foraged among the ships’ holds for food scraps. These were smaller relatives of the brown rats.

The initial outbreak of the plague in fourteenth-century Europe was the most virulent. In fact, much of the populations of England and France were decimated. In some parts of England the death toll was 50%. Some parts of France suffered an astounding loss of ninety percent of their populations.

Many modern readers assume that there was only one outbreak of the black plague, but there were actually several. In fact, it raged through Europe about once every generation until the beginning of the eighteenth century. One of the last major outbreaks occurred in England with the Great Plague of London, which took place in 1665-1666.

SOURCE: https://owlcation.com/humanities/Cats-and-the-Black-Plague