Human and Fungi genealogy, on today's Moment of Science.

Many times we tend to divide life into two main categories: plants and animals. And we're not alone. Scientists used to classify all living things that way too. You see, they assumed that living things that are similar in looks or build and probably share a common ancestry as well.

Every cell contains a structure called a ribosome which makes proteins, and the ribosome contains strands of RNA which carry the cell's genetic information. The greater the variation between the genetic sequences of two organisms' ribosomal RNA, the more distantly related they are, and the greater the evolutionary distance is between them.

When you classify organisms based on their genetic sequencing, you end up with three different kingdoms. The first is called bacteria, which contains microorganisms without a nucleus. The second is called archea, which also contains microorganisms without a nucleus, but their basic makeup resembles complex cells in plants and animals more than it resembles the makeup of bacteria.

The third kingdom contains all organisms whose cells have a nucleus, including plants, animals, algae, and even fungi. So evolutionarily speaking, humans and fungi are cousins.