Trivia

Hard

Foster’s Rule Is A Rule In Evolutionary Biology That Explains?

Mass Extinctions
Giant Island Creatures
Parallel Organism Development
Binocular Vision
A Haast's eagle attacking a pair of New Zealand moa.
John Megahan/Wikimedia

Answer: Giant Island Creatures

If you look closely at isolated islands and the current inhabitants (and fossil record) therein, a curious trend emerges. Creatures that migrate to the islands and live in isolation tend to end up either growing very large or very small, but few remain the original size of their mainland counterparts.

This phenomenon is called Foster’s rule after the 20th century biologist who first proposed it after extensive observation of size trends in island-dwelling animals. Foster noted that two things seemed to occur when a creature migrated to an island. Either the creature experienced insular giantism (it began growing larger on the island) or insular dwarfism (it began growing smaller on the island).

Typically, but not always, the trend aligns with whether the animal was a predator or prey. Foster’s explanation for this was simple and has held up over time: small prey animals could grow larger in the absence of abundant mainland predators and with plenty to eat on the island, whereas predators that experienced increased competition on the island became smaller, requiring fewer resources.

The painting here depicts two examples of (now extinct) giant adaptations, the Haast’s eagle and the flightless moa, both ancient species found in New Zealand.

Trivia

Easy

Which Of These Animals Was Originally Known As The “Water Horse”?

Trivia

Hard

If You’ve Received HTTP Status Code 418, It Means The Server Is?

Trivia

Easy

Lewis And Clark Expected To Find What Animal On Their Journey West?

Trivia

Easy

At One Time The U.S. Military Used What To Spot Heavily Camouflaged Enemies?

Trivia

Hard

The “A113” Easter Egg That Appears In Every Pixar Movie Is A Reference To?

Trivia

Very Hard

Electronic Arts Had To Recall A Tiger Woods Golf Game Because It Contained?

Trivia

Easy

In Russia Repurposed Fighter Jet Engines Are Used For?

Trivia

Easy

The Small Pocket In Blue Jeans Was Intended to Hold?

Trivia

Hard

SeaWorld Was Originally Intended To Be A?

Trivia

Hard

Which Country Has The Largest Tiger Population?