---
title: "List of common misconceptions about science, technology, and mathematics"
chunk: 3/16
source: "https://en.wikipedia.org/wiki/List_of_common_misconceptions_about_science,_technology,_and_mathematics"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:28:18.528573+00:00"
instance: "kb-cron"
---

The bold, powerful cry commonly associated with the bald eagle in popular culture is actually that of a red-tailed hawk. Bald eagle vocalizations are much softer and chirpier, and bear far more resemblance to the calls of gulls.
 Despite the saying "dumb as a dodo", the dodo's intelligence was above average for an avian, as it was a member of the family Columbidae (pigeons). The perceived stupidity of the dodo, a medium-sized flightless bird that was native to Mauritius, is due to naivety and passivity from living in isolation without significant predators.
Many believe that the dodo was hunted to extinction by European settlers due to its high culinary value. However, the dodo's meat was stated to be inedible by historical accounts, as one of its early names given by the Dutch was Walghvoghel (repulsive bird). The dodo's decline was caused more by predation of their eggs from invasive species as opposed to direct predation from humans.
A duck's quack actually does echo, although the echo may be difficult to hear for humans under some circumstances. Despite this, a British panel show compiling interesting facts was named Duck Quacks Don't Echo.
Ostriches do not stick their heads in the sand to hide from enemies or to sleep. This misconception's origins are uncertain but it was probably popularized by Pliny the Elder (23–79 CE), who wrote that ostriches "imagine, when they have thrust their head and neck into a bush, that the whole of their body is concealed".
Sixty common starlings were released in 1890 into New York's Central Park by Eugene Schieffelin, but there is no evidence that he was trying to introduce every bird species mentioned in the works of William Shakespeare into North America. This claim has been traced to an essay in 1948 by naturalist Edwin Way Teale, whose notes appear to indicate that it was speculation.

=== Other vertebrates ===
The skin of a chameleon is not adapted solely for camouflage purposes, nor can a chameleon change its skin color to match any background. Chameleons usually change color for social signaling, based on their mood, and for heat regulation. The use in social signaling may be to display bright colors for only brief periods of time to avoid increased visibility to predators.
Contrary to the allegorical story about the boiling frog, frogs die immediately when cast into boiling water, rather than leaping out; furthermore, frogs will attempt to escape cold water that is slowly heated before reaching their critical thermal maximum.
The Pacific tree frog and the Baja California chorus frog are some of the only frog species that make a "ribbit" sound. The misconception that all frogs, or at least all those found in North America, make this sound comes from its extensive use in Hollywood films.
The memory span of goldfish is much longer than just a few seconds. It is up to a few months long.
There is no credible evidence that the candiru, a South American parasitic catfish, can swim up a human urethra if one urinates in the water in which it lives. The sole documented case of such an incident, written in 1997, has been heavily criticized upon peer review, and this phenomenon is now largely considered a myth.
Pacus, South American fish related to piranhas, do not attack or feed on human testicles. This myth originated from a misinterpreted joke in a 2013 report of a pacu being found in Øresund, the strait between Sweden and Denmark, which claimed that the fish ate "nuts".
Piranhas do not eat only meat but are omnivorous, and they swim in schools only to defend themselves from predators and not to attack. They very rarely attack humans, only when under stress and feeling threatened, and even then, bites typically only occur on hands and feet.
Sharks can get cancer. The misconception that sharks do not get cancer was spread by the 1992 book Sharks Don't Get Cancer, which was used to sell extracts of shark cartilage as cancer prevention treatments. Reports of carcinomas in sharks exist, and current data does not support any conclusions about the incidence of tumors in sharks.
Great white sharks do not mistake human divers for seals or other pinnipeds. When attacking pinnipeds, the shark surfaces quickly and attacks violently. In contrast, attacks on humans are slower and less violent: the shark charges at a normal pace, bites, and swims off. Great white sharks have efficient eyesight and color vision; the bite is not predatory, but rather for identification of an unfamiliar object.
Snake jaws cannot unhinge. The posterior end of the lower jaw bones contains a quadrate bone, allowing jaw extension. The anterior tips of the lower jaw bones are joined by a flexible ligament allowing them to bow outwards, increasing the mouth gape.

=== Invertebrates ===