Intentional Harms Are Worse, Even When They’re Not

Predators are rare even when they are small

A recent review of published studies revealed that predators generally have lower population densities than non-predators in a variety of communities. We report here similar results for a highly replicated study of macroinvertebrates that colonized very uniform detrital microcosms in an old field. This pattern persisted even though predators usually were smaller than non-predators, as determine...

Even Accelerating Machines are Not Universal

We draw an analogy between Godel's Incompleteness Theorem in mathematics, and the impossibility of achieving a Universal Computer in computer science. Speci cally, Godel proved that there exist formal systems of mathematics that are consistent but not complete. In the same way, we show that there does not exist a general-purpose computer that is universal in the sense of being able to simulat...

Some properties are not even partially testable

For a property P and a sub-property P , we say that P is P -partially testable with q queries if there exists an algorithm that distinguishes, with high probability, inputs in P ′ from inputs ǫ-far from P by using q queries. There are natural properties that require many queries to test, but can be partitioned into a small number of subsets for which they are partially testable with very few qu...

Fertilization decreases plant biodiversity even when light is not limiting.

Many researchers hypothesize that plant richness declines at high soil fertility (and high productivity) due to light limitation. We tested this hypothesis in an old-field by independently manipulating fertilization and light levels via shade cloth (decreased light), vegetation tie-backs (increased light) and vegetation clipping (increased light). Droughts occurred during two of the four years ...

Pregnant, even when you did not want to be pregnant.