Schrodinger’s cat, thought experiments, and zombies
The best way to understand any complex scientific concept is to take a look at the thought experiments that refuted or expanded the theories behind it.
Later on, once the main idea is established in your head, the math that accompanies the science will be easier to grasp. This route is infinitely easier than plunging headlong into formulas and equations (which typically have more letters and symbols than numbers) while trying to discern their practical implications.
If we go a step further and marry that with something as universally adorable as pets, you’ll have no further excuses to avoid learning Quantum Mechanics, Cosmology, Classical Conditioning and various other behemoths of scientific edification.
Or so I tell my kids 🙂
Some famous scientific thought experiments involving animals:
 Schrodinger’s Cat– Erwin Schrodinger’s response to the Copenhagen Interpretation that impressed Einstein himself! It illustrates how some quantum concepts don’t work at nonquantum scales and helped define Quantum Indeterminacy or the “observer’s paradox”. Basically, a cat is trapped in a box with one Nitrogen 13 atom, a Geiger counter, and a mechanism to release poison gas if particle decay is detected. According to quantum mechanics, until the box is opened and its wave function is collapsed, the cat is 50% alive and 50% dead. Obviously, nothing but a zombie can be alive and dead at the same time, therefore “superposition” does not apply on a macroscopic level.
See also The Straight Dope’s epic poem, for an entertaining way to learn more on this.

Borel’s Monkeys– more popularly known as the Infinite Monkey Theorem: an infinite number of monkeys at a typewriter for an infinite time will “almost surely” come up with the complete works of William Shakespeare. While mathematically true, what are the chances of finding a working typewriter these days, let alone a Shakespearean monkey?

Hawking’s Turtles– from the beginning of Stephen Hawking’s A Brief History of Time: “A wellknown scientist (some say it was Bertrand Russell) once gave a public lecture on astronomy. He described how the earth orbits around the sun and how the sun, in turn, orbits around the center of a vast collection of stars called our galaxy. At the end of the lecture, a little old lady at the back of the room got up and said: ‘What you have told us is rubbish. The world is really a flat plate supported on the back of a giant tortoise.’ The scientist gave a superior smile before replying, ‘What is the tortoise standing on?’ ‘You’re very clever, young man, very clever,’ said the old lady. ‘But it’s turtles all the way down!'” In other words, beware of piling one unproven theory on another.

Pavlov’s Dogs– I know it’s not a thought experiment, but these are arguably the most renowned scientific animals the world over. Ivan Pavlov was a physicist whose close observations of drooling dogs turned his studies on the digestive system into extremely useful contributions to the field of Behavioral Sciences: Classical Conditioning and Involuntary Reflex Actions.
These books are fascinating reads on this particular subject:
Lastly, the best thing about thought experiments is that they cost nothing but your imagination and no animals are ever harmed in their making.