Broach the subject with many people and they would say they would be happy to hear of a world without rats. The reality is that life on this planet would alter significantly if all of the rats on the planet were to die. The net effect of such an occurrence would have ramifications that most people are not likely to have thought about.

Medical Research in a World Without Rats

Perhaps the most immediate impact on humans in a world without rats is in regard to medical research. The reality is that rats play a vital role when it comes to medical research.

95 percent of all lab animals are rodents, according to the Foundation for Biomedical Research. Rats are utilized in all types of medical research, from the development of new cancer drugs to dietary supplements and virtually everything else in between.

The primary reason why rats are so heavily relied upon for medical research is that the makeup of these rodents closely resembles that of humans. According to scientists, rats and humans have a great deal in common, including:

  • Genetics
  • Biological characteristics
  • Behavioral characteristics

In addition, scientists are able to breed rats that have been genetically altered. These are technically known as “transgenic rats.” These are rats that carry genes that are similar to those known to cause certain human diseases.

Rats are also broadly used in medical research because of what researchers generally consider convenience. Rats are used because they are:

  • Small
  • Easily housed
  • Have short lifespans (two to three years)

The Spread of Disease and Rats

The complete elimination of rats on the planet would alter the manner in which some diseases occur among human beings. Rats are responsible for spreading certain viruses and bacteria, some of which cause serious and even fatal diseases.

The hantavirus can be used to illustrate how the lack of rats on the planet potentially could slow the spread of hantavirus. Hantavirus is spread through rat droppings. The math is simple: No rats, no rat droppings, no ability to transmit hantavirus from rats through rat droppings.

This equation is only part of the story, however. Viruses have proven themselves to be highly adaptable pathogens. Time and again, when a virus loses a means of transmission, the virus mutates in some manner allowing for other pathways of infection. The same can be reasonably expected to happen if all rats were eliminated from Earth.

In addition, the question here is what would happen if rats were eliminated, a query which presupposes that mice would carry on in existence. Most viruses are that is transmitted by rats are also capable of being transmitted by mice.

As the rat population declines to nil, odds are the mice population would increase. Viruses that perhaps once were more commonly transferred via rats would migrate to mice as the primary host.

Ecological System Out of Whack

If all of the rats on the planet were to suddenly die, the ecological system in many places around the world would be thrown out of whack. For example, the population of those living things that rats prey on for sustenance would increase in number due to the lack of a natural predator. On the other hand, those animals that preyed on rats would be without a food source. In short, the ecosystem food chain would be thrown into a state of disruption, at least for a period of time.

In addition to disrupting the ecosystem food chain, if all rats on the planet died, flora or plants across the globe would be disrupted. Rats play a role in seed distribution. Rats ingest items that contain seeds, many seeds then passing out of their bodies intact via rat droppings.

Unexpected and Unintended Consequences

In the final analysis, when honestly addressing the question of what happens if all rats on the Earth die, we simply do not know. Yes, there are some consequences that can reasonably be anticipated – good and bad. However, if all of the rats on the planet were eliminated there would be both unexpected and unintended consequences (unintended consequences meaning that there was some sort of coordinated effort to eradicate rats).

At different junctures in history, efforts were made to eradicate the rat population. For example, there was a concerted effort to do this in Europe during the era of the Black Death or bubonic plague. Immediate health issues may call for the eradication of rats. However, the complete elimination of the species very well may have highly negative unexpected, unintended consequences.