I Contain Multitudes

The breakdown of the symbiosis between host and pathogen.

Evolution is change over time. It refers to the change in biological populations through the slow process of natural selection. 

The ability of an individual to survive, thrive, and reproduce.

A way of raising lab animals to determine the importance of microbes in an animal. This allows researchers to determine what happens when an animal is deprived of microbes, as well as what happens when specific microbes are added. 

The combination of a host and microbes as one whole unit or being.

The total of all an individual’s genes plus their microbe’s genes, used to analyze the genome of the holobiont.

The transfer of DNA/genes from one individual to another not using sexual reproduction. Bacteria do this by creating bridges between themselves and shuttling DNA between each other. 

Human Milk Oligosaccharides (HMOs) are complex sugars that all mammals make in their milk. Humans create more than their mammalian counterparts. They represent the third-biggest part of milk, and babies cannot digest them, but they feed bacteria in our gut. 

The idea that children in developed countries don’t come in contact with as many infectious diseases because of more cleaning and antibiotic use. This lack of exposure leads to an immune system that will react to harmless substances. 

The study of the genome of communities, specifically used in the context of the microbiome. Coined by Jo Handelsman.

Natural selection is the process that leads to evolution. There must be variations between individuals in the population, those variations must be heritable, and they must impact the fitness of the individual. 

A probiotic is bacteria taken to benefit health.

The partnership between living things. This term is inherently neutral and implies all forms of existing together.