74 DISCOVERMAGAZINE.COM
20 Things You Didn’t Know About ...
described how the excrement of giant pandas was
“ideal” for biofuel production. 12 The bears digest
bamboo, thanks to unique gut microbes that break
down the tough plant material. Once excreted and
cultured by researchers, those same bugs go to town
on other plant scraps and produce a hydrogen-based
biofuel. 13 That’s a pretty ingenious way to fuel
an engine. Both words, by the way, derive from
ingenium, Latin for “talent,” an abstract concept.
Over time, the word engine also took on the more
concrete meaning of a device. 14 A device you
don’t see much these days is the siege engine. For
millennia, these massive military weapons, such as
catapults and battering rams, were a popular way to
breach defenses. 15 One engine that has catapulted
to fame in the last couple of decades isn’t an engine
at all. Search engines, programs that provide you
with lists of websites based on the terms you tell it to
find, aren’t converting energy so much as directing
curiosity. 16 In 1989, McGill University graduate
student and systems administrator Alan Emtage
needed an efficient way to find files spread across
multiple servers. He created a program to hunt
through the servers for specific content he requested.
17 Emtage’s personal timesaver got a big promotion
when his boss recognized its potential. The McGill
team expanded the program — known as Archie, a
shortened form of “archive” — into the world’s first
search engine. 18 Technology gave us another engine
that’s not really an engine. Developers use software
packages called game engines as the template for
the world in which a video game is set. 19 These
complex programs automatically regulate the basics
of a game, from managing memory needs efficiently
for smoother play to changing the lighting as a char-
acter moves through a landscape. 20 Scientists are
increasingly turning to game engines in their research
because the programs are, by nature, fast and
efficient at tasks such as visualization. In 2017, for
example, researchers designed a game engine-based
system to identify optimal wind turbine positioning.
There it is: more human ingenuity.^ DGemma Tarlach is senior editor at Discover.1 Everybody’s doing the locomotion... really. We are all engines, which by
their most basic definition are machines
that convert energy into motion. 2 And
while you could think of animals as
being engines, plants have them:
Photosynthesis pathways are often
described as plant engines, and
biologists are particularly interested
in the C 4 plant engine, which was
discovered in the 1960s. 3 Plants
powered by C 4 engines, including maize and sugar
cane, typically convert atmospheric carbon dioxide
more readily, thanks to novel leaf and cell structures.
They also tend to produce higher yields than C 3
species, which outnumber C 4 species by about 30
to 1. 4 The C 4 pathway evolved multiple times
in different lineages, often during periods of low
carbon dioxide or in semiarid environments. The
adaptation allows the plant to use scant resources,
such as water and nitrogen, more efficiently. 5 And
that’s why scientists are using genetic modification
to try to turn C 3 plants into C 4 powerhouses, which
may prove more resilient in a drier, resource-depleted
world. 6 If thinking of plants as having engines is
a little out there for you, how about a really far-out
fact: Black holes are the universe’s most powerful
engines. 7 The workings of a black hole are similar
to an internal combustion engine.
It consumes fuel and produces
energy while remaining intact,
unlike, say, an explosion. 8 How
can a black hole produce energy
when nothing escapes it? Well, once material falls in,
there’s no going back, but the black hole’s extreme
gravity creates the perfect environment for generating
energy just outside its boundary, or horizon. 9 In
2009, two researchers proposed a highly theoretical
spacecraft powered by multiple mini-black holes
— the smaller a black hole is, the more energy it
produces. 10 While the idea caused a buzz initially,
the concept remains theoretical. Quite frankly,
we’re more likely to have engines that run on panda
poop. 11 No, seriously. In a 2016 study, researchers
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53187-1612. Printed in the U.S.A. FROM TOP: NASA’S GODDARD SPACE FLIGHT CENTER; DAUKER/DREAMSTIME; PRILLFOTO/DREAMSTIME; DAN BISHOP/DISCOVEREnginesBY GEMMA TARLACH
From top: Black
holes, catapults and
plant pathways
may not be what
powers your daily
commute, but they
still convert energy
and are technically
all engines; despite
being called “search
engines,” however,
online queries and
search functions
don’t meet the
definition.