DOGS!
I love them! They're probably the internet's second favorite animal
... Just slightly behind cats and ahead of honey badgers
and foxes and angry emus
And if there'a a dog with you right now watching me,
it turns out that he or she might be listening to me
pretty much in the same way that you are!
HI... DOG!
When you listen to me talk-- I'm talking to the human now, not the dog anymore--
When YOU listen to me talk,
You're hearing more than just the words that are coming out of my mouth.
You're also hearing the tones of my voice
and that's giving you clues to my gender, and clues to my emotional state.
Am happy? Or sad? Or excited?
All these little tones are called prosodic cues
They involve the elements of speech that are less about meaning and more about rhythm
and stress, and intonation.
Phonetic cues, meanwhile, are what help us to understand the actual words
and the meanings behind them
Our studies have already found that dogs process things like rhythm and intonation when they listen to other dogs.
And this week scientists have announced that they do the same thing when listening to us.
It's really cool how they did it.
Biologists at the University of Sussex tested dogs' listening abilities by analyzing
how more than 200 canines responded to prerecorded samples of human speech.
They had each pup stand between a pair of speakers, and then played recordings of different people saying different phrases.
Some with a lot of prosodic cues, while others were read in an atonal, almost robotic voice.
The scientists predicted that the dogs would probably turn their heads to the left speaker
when they heard one type of voice, and to the right speaker, when they heard the other.
Now, that's weird, but it's because the more emotion-based prosodic cues are thought to be processed by the right hemisphere or the brain,
while the meaning-based phonetic cues are processed by the left hemisphere.
So when a command like, "Come on, man" was played in an atonal voice, 80% of the dogs
looked at the right speaker, suggesting that the command was registered in the left hemisphere of the brain
Cause, remember, the sound heard by one ear is transmitted to the opposite side the brain.
But when the same phrase were said in a happy, expressive human way, the dogs looked at the left speaker
indicating that they were processing the prosodic cues on the right side of the brain.
Which is just how we do it!
So, obviously, your dog understands everything you say, right? No.
But it does suggest that there's a lot more information processing going on behind those adoring eyes
and lolling tongue than you might think.
Now, your dog probably has it's own adorable way of getting out of trouble when you get mad,
but one of the coolest avoidance strategies in the animal kingdom belongs to another creature on the news this week.
The pufferfish!
There are more than 120 species of pufferfish around the world,
mostly found in warm waters and they're almost all as poisonous in real life as they are in Minecraft.
But until now, we weren't really sure how they performed their namesake trick,
inflating their bodies to 3 or 4 times their normal size.
When a pufferfish sees a potential threat, like a tiger shark or a scuba diver,
they start quickly gulping up water.
As they ingest that water, their highly elastic stomach expands, nearly quadrupling their body's volume.
Most scientists thought that puffers managed to hold this water by basically doing what they look like--
they're holding their breath.
That's because some studies have found that puffers' gill slits, actually called "opercula valves",
clamped shut when they are in full-puff mode, suggesting they have to stop breathing in order to hold the water inside.
Which would be amazing if it were true, because a puffer can stay inflated for 20 to 30 minutes.
But! A new study of black-saddled pufferfish, native to the Indian ocean,
has found that there's something else going on here.
Scientists from the James Cook University in Australia studied black-saddled puffers in special tanks called
"respirometers", which can measure how quickly fish respire oxygen.
Every 5 to 10 minutes the tank was flushed with oxygenated water,
the biologists then measured how much oxygen was consumed between flushes to figure out how much the fish were breathing.
They found that, when inflated, the puffers are using up to 5 times more oxygen than in the deflated state,
and their gills were still moving.
So, the biologists now think that black-saddled puffers have a specialized sphincter in their esophagus,
which they can close to keep the water in their stomachs while allowing the gills to keep working.
The study have also found that this amazing ability comes at a cost.
It seems that getting in staying inflated is exhausting.
The puffers breathed a lot harder when they were gulping water into their stomachs.
So hard, in fact, that it took 5.5 hours for their oxygen levels to return to normal.
So, if you see a puffer on your next snorkeling trip, just leave the poor guy alone.
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