By the year 1840, Ireland’s population had grown to 8 million. According to the PowerPoint shown in class, over half of Ireland’s huge population in 1840 was entirely dependent on the potato. Its nutrition content is such that people were able to survive on potatoes for all meals, perhaps with the occasional bit of milk. Most of the best products were forcibly exported to England, and thus landowners were forced to work their laborers harder to keep themselves financially afloat under such requirements. Poverty skyrocketed, and those in poverty were forced to live in crowded, slum-like conditions. To make matters worse, potato production focused on one or two high-yielding varieties. Though it may have at first seemed to maximize production and profit, this monoculture made the plants highly susceptible to disease.

Starting in 1845, the potato blight struck: a fungus-like organism called Phytophthora infestans, resulting in shrunken, corky, and rotted potatoes. Somewhere between a third and a half of potato crops were lost in 1845, and three-quarters of crops in 1846. In the years that followed, much of the seed potatoes (ie those able to sprout new potato plants and thereby revive potato production) were damaged and unable to assist in Ireland’s recovery. As described in the PowerPoint from class, P. infestans is believed to have originated in Mexico, spread to North America, and then crossed the Atlantic in potatoes used as provisions for the long voyage. The strain which caused blight (HERB-1) continued to spread until the 1970s, after which it died out and has since been replaced by the US-1 strain, a descendant the same original P. infestans strain from Mexico.

Irish people were forced into further poverty and malnutrition by the blight. Diseases listed in the PowerPoint such as measles, tuberculosis, diarrhea, whooping cough, and respiratory infections became common as a result of malnutrition, and cholera struck Ireland in 1849. Over a million people died, and another million (amounting to 20-25% population loss overall) emigrated from Ireland in hopes of escaping the blight. The United States was a common destination for refugees from the blight, and they brought many of the above listed diseases to the US on so-called “coffin ships” where few people survived to see the New World. As a result, Irish slums in the US became more prevalent and filled with disease.

Today, potatoes can be genetically engineered against blight (as described in the article “EPA, FDA approve 3 types of genetically engineered potatoes” by Keith Rogers in 2017). Still, many people are not fond of the idea of altering nature to create such GMOs (Genetically Modified Organisms). Another contemporary example of the GMO controversy is described in the 2019 NPR article by Rob Stein (“Scientists Release Controversial Genetically Modified Mosquitoes In High-Security Lab”). Stein explains that scientists have genetically modified some female mosquitos to have male mouthparts and deformed sexual organs, a characteristic that will be passed on to all offspring. The hope for this genetically modified mosquito is that it can greatly decrease mosquito populations and stop the transmission of malaria in Africa. Regardless, critics worry about unexpected ecological effects such as changes in pollinator populations or potential emergence of mosquitoes carrying other diseases. For now, the new “gene-drive” mosquitoes are simply being studied in Italy, a climate in which they would not be able to survive even if they escaped the lab. With more study and perhaps a few adjustments, scientists hope they can gain approval to release the mosquitoes in malaria-stricken areas.

HR: References as listed in text, class discussion, Microsoft Word for spelling/grammar check