Speaker 1: Welcome to brain Stuff, a production of I Heart Radio,
Speaker 1: Hey brain Stuff Lauren Vogelbaum. Here, most dogs and cats
Speaker 1: are never late for a meal. They know exactly where
Speaker 1: to be at the same time every day. They also
Speaker 1: know their owner's schedules, and, like clockwork, will join you
Speaker 1: in or even anticipate your daily movements, like waiting by
Speaker 1: the door when you usually get home from work, or
Speaker 1: complaining if it's bedtime and you're still up. When you
Speaker 1: witness this behavior, you might assume that your pet has
Speaker 1: a sophisticated understanding of time, But what is time really
Speaker 1: like for a dog or cat. To understand how animals
Speaker 1: perceive time, we first need to understand how humans perceive time. Arguably,
Speaker 1: each person experiences the passing of time in different ways
Speaker 1: at different times. Albert Einstein once explained the principle of
Speaker 1: relativity by saying, when a man sits with a pretty
Speaker 1: girl for an hour, it seems like a minute. But
Speaker 1: let him sit on a hot stove for a minute,
Speaker 1: and it's longer than any hour. That's relativity. Even though
Speaker 1: the experience of time is relative for every individual, all
Speaker 1: humans probably think about time in similar ways. For instance,
Speaker 1: our memories are inextricably tied to how we understand the
Speaker 1: passing of time. Our ability to remember events in a
Speaker 1: particular order plays a large part in our perception of time.
Speaker 1: We're also able to predict things not in a psychic way.
Speaker 1: Each of us makes educated assumptions about certain events in
Speaker 1: the future, even as simple as assuming that the sun
Speaker 1: will come up tomorrow. These abilities have important implications. For instance,
Speaker 1: memory and prediction allow us to have a sense of
Speaker 1: continuity of personal history and self awareness. So do dogs,
Speaker 1: Cats and other animals have the same abilities. If you
Speaker 1: climbed inside of a dog's mind, would you be presented
Speaker 1: with the memory of eating a raw hide bone earlier
Speaker 1: this morning. Research on how dogs and cats in particularly
Speaker 1: perceived time is limited, but we can learn more about
Speaker 1: it when we look at the extensive research that's been
Speaker 1: done with other animals, such as broad birds and primates.
Speaker 1: Animal cognition researcher William Roberts has made some remarkable conclusions
Speaker 1: regarding animal memories and anticipation. He says that animals are
Speaker 1: stuck in time. By this, he means that without the
Speaker 1: sophisticated abilities it takes to perceive time, like truly forming memories,
Speaker 1: animals only live in the present. Roberts thinks animals are
Speaker 1: stuck in time because they can't mentally time travel backward
Speaker 1: or forward. Humans can consciously and willfully think back to
Speaker 1: specific memories and anticipate new events. Animals cannot, too many.
Speaker 1: This might seem like a faulty theory. After all, can't
Speaker 1: we train animals and doesn't this training depend on animals
Speaker 1: own memories? Well, not necessarily, at least not in the
Speaker 1: way we usually think of memories. According to Roberts, animals
Speaker 1: might be trained to do things in the same way
Speaker 1: that young children are trained to do things. According to
Speaker 1: studies with children, by the age of four, kids have
Speaker 1: learned lots of things crawling, walking, but without them toll
Speaker 1: ability to remember where or how they learned them. In
Speaker 1: other words, they don't have the power of episodic memory,
Speaker 1: or the ability to remember particular events in the past.
Speaker 1: A dog can know how to respond to the command
Speaker 1: sit without having a memory of the specific event in
Speaker 1: which it learned that command. And that's not all that's
Speaker 1: at work in a dog or cat's brain to help it,
Speaker 1: for example, impeccably predict the arrival of its owner. Internal
Speaker 1: biological rhythms also play their part. According to Robert's researchers
Speaker 1: have discovered from experiments on pigeons that an internal clock
Speaker 1: allowed the birds to learn where and when food would
Speaker 1: be available. Similarly, our furry friends might use circadian oscillators,
Speaker 1: that is, daily fluctuations of hormones, body temperature, and neural
Speaker 1: activity to know when food is likely to hit the
Speaker 1: bowl or when owners are likely to return home. Instead
Speaker 1: of remembering how much time passes between meals or what
Speaker 1: time meals are given, dogs and cats react to a
Speaker 1: biological state that they reach at a particular time of day,
Speaker 1: and they react the same way at the same time
Speaker 1: every day to the stimulus. So if they can't store
Speaker 1: memories like humans can, can they plan for the future.
Speaker 1: In his work, Roberts argues that time is a human
Speaker 1: construction created to keep track of such things as days
Speaker 1: and significant events. A timekeeping devices from sundials and precise
Speaker 1: clocks to smartphones have revolutionized how humans perceived time, and
Speaker 1: animals don't have the advantage of these tools. Human beings
Speaker 1: have two important abilities to help us understand time. We
Speaker 1: are able to remember a sequence of events, and we
Speaker 1: are able to anticipate future needs or events. Studies show
Speaker 1: that animals may have these abilities, but to a lesser extent.
Speaker 1: Scientists have tested animals working memories and reference memories, that is,
Speaker 1: their short term and long term memory, respectively. They did
Speaker 1: this to see how well the animals recall sequences of events.
Speaker 1: In working memory tests, for example, pigeons or primates have
Speaker 1: been encouraged to remember a sequence well enough to pick
Speaker 1: or pick it in the right order again to get
Speaker 1: a reward. The animals did fairly well at these tasks,
Speaker 1: but their memory faded fast. Roberts thinks that they were
Speaker 1: probably learning going from weakest memory to strongest memory, rather
Speaker 1: than actually learning or remembering a sequence. Other researchers found
Speaker 1: that pigeons and monkeys performed well at reference memory tests,
Speaker 1: in which they needed to remember a sequence after a
Speaker 1: delay between learning and testing, but it took extensive training
Speaker 1: for the animals to learn these sequences, suggesting to Roberts
Speaker 1: that the ability did not come naturally to them. From
Speaker 1: these tests, it seems that animals would perceive time differently
Speaker 1: from humans, who have a relatively reliable and sophisticated memory
Speaker 1: of a sequence of events. In addition, animals don't seem
Speaker 1: to anticipate future needs and rewards very well, suggesting to
Speaker 1: researchers that they don't have a concept of the future.
Speaker 1: For instance, when given the choice, pigeons and rats shows
Speaker 1: a smaller immediate reward over a larger future reward. In
Speaker 1: one test, researchers presented primates with a choice between one
Speaker 1: banana and two bananas. Understandably, they chose to bananas consistently. However,
Speaker 1: as the supply of the two choices got larger, they
Speaker 1: started showing less of a preference. They weren't hungry enough
Speaker 1: at that moment to eat ten bananas, so they chose
Speaker 1: five bananas about half the time. Roberts concludes from these
Speaker 1: experiments that these animals sought to satisfy immediate hunger needs
Speaker 1: and weren't planning for future hunger. This is very unlike humans,
Speaker 1: who often use reason and forethought to anticipate future needs,
Speaker 1: from packing a snack and a drink for later to
Speaker 1: investing in a retirement plan. So what about squirrels and
Speaker 1: other animals that hoard food for the impending winter months.
Speaker 1: That behavior seems to imply that the animals anticipate future needs,
Speaker 1: but maybe that's not it studies have found that animals
Speaker 1: don't stop hoarding even when their supplies disappear over and
Speaker 1: over again. This could mean that the animals don't understand
Speaker 1: why they hoard, what it means for their future, or
Speaker 1: in what the future is. They simply do it out
Speaker 1: of instinct. Humans, on the other hand, understand their preparations
Speaker 1: and will quickly change strategies when their plans go awry.
Speaker 1: If animals are stuck in time, as Robert suggests, this
Speaker 1: could mean that understanding time is uniquely and fundamentally human.
Speaker 1: Today's episode was written by Jane McGrath and produced by
Speaker 1: Tyler Clang. For more on this a lot of other
Speaker 1: curious topics, visit how stuff works dot com. Brain Stuff
Speaker 1: is production of iHeart Radio or more podcasts. My Heart
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Speaker 1: you listen to your favorite shows.