After being
awake for many hours or days, humans and most other mammals are forced to stop
all activity and sleep deeply. This involves a total stop of activity, a
deactivation of skeletal muscles, and a processing of memories. However, it
turns out, not all mammals have this need. Dolphins can stay alert for more
than two weeks without going into a complete, deeps sleep. They apparently do
this by sleeping with only half of their brains at a time. This makes sense,
because if dolphins slept like we do, they would be easy prey to sharks.
However, the fact that they can effectively stay awake possibly indefinitely is
amazing.
Researchers in
San Diego decided to look into Dolphin sleep more in depth in a study they did
in 2008. The scientists had two dolphins — a female, Say, and a male, Nay —
continuously scan the tanks they were in using echolocation. If they detected objects
in the water, they were trained over the course of a year to press a paddle to
get fish. The scientists found these dolphins could use echolocation with
near-perfect accuracy and no sign of tiring for up to 15 days. And 15 days was
just the length of the study; it is possible that dolphins do this their entire
lifetimes! It is absolutely amazing the diversity of life on this planet, and
the adaptations that animals have.
-JE
I did not know that dolphins could go 2 weeks at a time without complete sleep! That is crazy! I can't imagine what life would be like if we could stay awake for 2 weeks at a time. Are there other reasons why dolphins stay awake for that long besides avoiding sharks?
ReplyDeletePosted by Amber Vien
Dolphins are just like all other mammals, in that they must breathe. So, they need to stay awake for that as well.Also, it seems like it would be useful for a dolphin to stay awake to feed!
Delete-JE
Interesting post! I agree with you that adaptation is one of the most amazing ability that organisms can have. I think this adaptation of dolphins developed when they returned to the ocean from land. Not just because their behavior is rarely seen in mammals, but also it is quite common for marine organisms. Fishes generally need much less time to rest comparing to mammals. Do you think dolphins might have found another to way to rest without a total stop of activity?
ReplyDeletePost by Yim Hui
I didn't know that dolphins could stay awake this long. I wonder if other marine animals have similar adaptations like this? Wouldn't it be interesting if people could stay awake for lengthy periods of time like this!
ReplyDeletePosted by Morgan Matuszko
It would be pretty cool if humans did not need to sleep. But then again,sleeping helps us process our memories, and give our bodies time to heal. Dolphins would probably do well if they had a time and place to have deep sleep, but they can't out of necessity.
Delete-JE
Very interesting post, I have actually heard about a dolphin's ability to use half of their brains at a time, in order to rest the other half and avoid the need to sleep. Are there any other known species that are able to perform the same, or similar, mechanism?
ReplyDeletePosted by Kristen Whitehead
It seems that many species of marine mammals never go fully to sleep. Whales are another group of animals which do something like the partial sleep of dolphins. It is just that dolphins are the most famous!
Delete-JE
I didn't know that dolphins slept with only half their brain! Also, I read somewhere that dolphins can actually recognize themselves in a mirror as well. Do you know of any other animals that exhibit some of the same behaviors?
ReplyDeletePosted by: Lindsey Janof
Really cool stuff. I'm wondering how it's possible to rest half of the brain at a time. Have there been studies if there are other species that are capable of doing that?
ReplyDelete-Samuel Ustayev