|Do animals need sun or not?|
|Question Date: 2018-02-14|
Animals are heterotrophs, which means
that they eat other things, so it's possible for
animals to live without sunlight (for a while at
least). They rely on the sun indirectly, however,
because the stuff that animals eat depend on
sunlight. Cows, for example, eat grass, which
requires sunlight to grow (plants are
autotrophs --they create their own food
through photosynthesis, which requires
sunlight). Foxes eat mice and birds. Like
foxes, mice and birds don't need light to live,
but the seeds and other things that mice and
birds eat do night light. Food is a source of
energy for animals. The ultimate source of energy
is sunlight, so in that respect, animals DO
This question sounds like it arises essentially
from confusion over where animals get their
energy. Unfortunately, the answer is not a simple
yes or no. It is true that most (in fact, nearly
all) animals do not need the sun directly, because
they get their energy from food they eat. However,
the base of the food chain is made up almost
entirely of plants which produce their food using
energy they get from the sun. For the most
part, this includes caves and the depths of the
ocean, because the decaying matter and waste
consumed by the resident animals initially came
from some location which did have sunlight.
However, some locations in the ocean have
deep-sea hydrothermal vents which are home
to ecosystems that apparently do not require any
energy from the sun.
Certain specialized bacteria and microorganisms
are able to convert minerals expelled by the vents
into usable energy and then become food for other
animals living in around the vents. There are also
some caves which have ecosystems ultimately
based on chemical energy sources rather
than the sun.
The question to this answer depends on how we
define the word "animal". If we define "animal" as
"all the organisms that belong to the Animalia
Kingdom according to current biological
classification systems", then no - not all animals
need the sun. The ones that we normally consider
as animals - dogs, cats, birds, spiders - these
certain need some sun. However, there are
deep-sea creatures that are also in the kingdom of
Animalia that do not need the sun at all.
Sunlight cannot penetrate so far into the sea, so
for these animals to survive, they must develop
ways to survive without the sun. The angler fish
(scary looking creature with lots of sharp teeth)
is such an example.
That's an interesting question. Plants need
sunlight to do photosynthesis to make food for
animals to eat, but animals don't do
Some animals get no sunlight. Fish in the
deep ocean, for example. People sometimes get
sad, in dark winters, and light from bright lights
makes them happier.
This question does not have a "yes" or "no"
Animals need warmth, and animals need food. The
sun provides warmth, but isn't the only way to be
warm. The sun provides light that plants or
algae need to grow, and almost all animals eat
either plants or algae. This means that,
without sun, most animals would die because the
plants would die. There are a few animals that
eat bacteria that eat chemicals from the hot inner
Earth, and they may not need sun.
Yes, we animals do need the sun. It keeps
us warm. The light from the sun gets trapped
inside our atmosphere and gives us heat.
We also need the sun because plants need the
sun and we need plants. The sun gives plants
the energy they need to grow. Plants can take
the carbon dioxide we breathe out and water from
the soil, and make sugars, starches, and all sorts
of other molecules that we eat. They also produce
oxygen, which we need to breathe. Without
plants, we would starve and suffocate.
Here’s a fun thought experiment. Think about
some form of energy and I’ll bet you can trace it
back to the sun. Example: The school bus needs
energy. It gets energy from gasoline. Gasoline is
the remains of dinosaurs and other animals that
lived millions of years ago. The dinosaurs ate
other dinosaurs or plants, which got their energy
from the sun.
Your turn. Can you think of any types of
energy that don’t come from the sun?
Thanks for asking,
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