The cat-fall chart that only counted the survivors

A 1987 vet study found that cats falling from higher floors arrived with fewer injuries — so the penthouse looks safest. The catch: the cats that died on impact never arrived to be counted.

Whitney & Mehlhaff, “High-rise syndrome in cats,” J. Am. Vet. Med. Assoc., 1987Added July 8, 2026

Line chart titled “Why your cat wants the top floor” plotting average injuries per cat against stories fallen; the line climbs from 0.76 injuries at 2 stories to a peak of 2.4 at 7–8 stories, then a red arrow plunges to 1.1 at 9–32 stories, beside a cartoon cat asking for “Top floor, please” and a caption reading “Higher is safer!” — Exhibit A — as published

The same curve redrawn in grey with hollow markers; a hatched red band over the 9–32-story column is labelled “NOT HERE: cats killed on impact”, with a note explaining the clinic only ever met cats that arrived alive, so the dip at high floors is a survivor’s curve, not safety — Exhibit B — the honest redraw

The claim

The higher a cat falls from, the less it gets hurt: injuries climb until about the seventh floor, then drop by half for longer falls — so a cat is safest up in the penthouse.

The trick

The dataset is cats brought in to a Manhattan animal hospital — which means cats that survived the fall. A cat killed on impact is rarely carried to a vet, so it never becomes a point on the chart. High falls are the ones most likely to kill outright, so it is precisely those deaths that go missing, and their absence drags the average injury count for the top bin down. The dip at 9–32 stories isn’t cats getting safer; it’s the worst outcomes quietly leaving the sample. (It doesn’t help that 24 floors of data are squashed into a single point drawn from very few, very lucky cats.)

The honest version

The honest redraw keeps the identical points but shades the region the data can’t see — the cats killed on the way down, absent from every marker. Read carefully, the real finding is only “among cats that reached the clinic alive, the ones from higher falls arrived with fewer injuries,” which is a long way from “higher is safer.” There may well be a genuine effect too — cats seem to hit terminal velocity around five stories, then relax and splay out to spread the impact — but a survivors-only sample can’t tell you how big it is. To measure that, you’d need the cats that never arrived.