xkcd.WTF!?

Explanation ➲

This comic indulges in some wordplay on the title of the 1988 animated movie The Land Before Time, which takes place millions of years ago in the time of dinosaurs.

The comic shows a timeline of the history of the universe from the Big Bang to the present day, with The Land Before Time placed at the point in the timeline where the movie is set, as well as other seemingly arbitrary events such as the formation of rocky planets and the evolution of ground-nesting bees. The joke is that Randall has contrived several periods of universal history that sound like funny permutations of "The Land Before Time" due to certain words being homophones, such as "time" and "thyme", or homonyms, such as the noun "land" (ground) and the verb "land" (to alight). He also split the word "before" into "bee" and "for".

The title text is for the phrase "the time for Beeland" and lists 2 places (that Randall found on Google) with the name "Beeland": a market in Spillimacheen, British Columbia or a chalet in Slovenia.

Bees are a recurring topic on xkcd.

Explanation of time ranges on the chart

Range	From	To	Explanation
The time before land	Big Bang	Rocky planets form	The Big Bang is a scientific theory that attempts to describe the very earliest conditions in our universe, but is also used informally as a synonym for the beginning of the universe. The early universe contained only simple elements such as hydrogen, but over time, star formation led to the creation of new, heavier elements, which eventually gave rise to planets with a rocky surface, which we call "land". It would have taken billions of years for the first such land-bearing planet to appear in the universe, so this time period could be considered "the time before land".
The time before bees	Big Bang	Ground-nesting bees evolve	This time range also includes the formation of the Earth, a necessary precondition for bees to evolve.[citation needed] Any time before the evolution of bees could be considered "The time before bees". While the chart does not account for the possibility that non-ground-nesting bees may have existed prior to ground-nesting ones, evidence strongly suggests that the common ancestor to all bees nested in the ground rather than forming hives.
The land before thyme	Rocky planets form	Thymus genus diverges	Thymus is the genus of plant that is called "thyme" in English, and it is pronounced exactly the same way as "time". By "diverges", it is meant that this is the point in time at which the Thymus genus of plants split off from their ancestral line - ie. when thyme first evolved. This time range is after land first appears in the universe, but before thyme evolved - therefore, any land that existed within this time range can be considered "the land before thyme". When said, this sounds exactly the same as "The Land Before Time".
Time for land bees!	Ground-nesting bees evolve	Now	When conditions change to allow an event to occur, people sometimes say "time for (event)!". In this case, the event is the emergence of ground-nesting bees, which could be considered "land bees".
Bees land on thyme	Thymus genus diverges	Now	Bees are flying insects, and therefore must land in order to rest before taking off again. Now that thyme has evolved, bees are able to land on thyme plants. This is a play on two different meanings of the word "land"; as a noun, it means solid ground, but here, it is a verb which means to alight or stop flying. There is also a secondary joke here, with thyme sounding similar to time. Such, bees landing on thyme could be misheard as bees not landing late.