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spring fever
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that's full of energy, vitality
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and sexual appetite associated with spring
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it's been written about for centuries
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but does it really exist?
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there's definitely something in this spring time air
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a Canadian study showed a way that
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teen pregnancy peaks in March
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right around spring break
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and the another found that men
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produce the most
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and the healthiest sperm
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in early spring
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what's causing this seasonal shift?
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Scientists think our increase in
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energy and better mood
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have to do with changes in hormone levels
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an important one is melatonin
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sometimes called the "sleep hormone"
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it's released at night and helps us to fall asleep
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when the nights are longer
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we produce more melatonin
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and in spring, as the night gets shorter
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we produce less of it
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may be explaining why we feel
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more awake and more active
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seratonin is another chemical
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that affects our mood
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it's known as the "happiness hormone"
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and it's level risens in spring time
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as it gets sunnier
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and the pathologists think that
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this changes in hormone levels
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may have to do with survival and
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reproduction
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many animals lay low in the winter
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using less energy because food is sacarce
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early humans might have done the same
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when food became more abundant in the spring
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and it make sense that they become...
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more....
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active
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not surprisingly
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as you move toward the equator
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spring fever disappears
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for example
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scientists have noticed that seasonal changes
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and the birth rates of field mice
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flatten out
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as you get closer to the equator
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but sunshine may not be the only
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spring time "pick me up"
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for humans, the optimal temperature for
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good mood is 72 degree Fahrenheit
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and let's face it
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once the temperature starts to rise
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we're wearing a lot less
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for Scientific Americans and Instant Egghead
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I'm Yasmin Tayag