A spring fever
that boost of energy, vitality and sexual appetite
associated with spring.
It's been written about for centuries.
but does it really exist?
There's definately something in the springtime air
A Canadian study showed that
the rate of teen pregnancy peaks in March.
Right around spring break.
And another found, that men produce the most
and the healthiest sperm in early spring.
What's causing this seasonal shift?
Scientists think, that our increased energy and better mood
have to do with changes in hormone levels.
An important one is melatonin
sometimes called the "sleep hormone"
It's realeased at night and helps us fall asleep.
When the nights are longer
we produce more melatonin.
And in spring, as the nights get shorter,
we produce less of it.
Maybe explaining why we feel more awake and more active.
Serotonin is another chemical that affects our mood.
It's known as the "happiness hormone"
And its levels arise in spring time as it gets sunnier.
Antrophologists think that these changes in hormone levels
may have to do with survival and reproduction.
Many animals lay low in the winter
using less energy because food is scarce.
Early humans might have done the same.
And when food became more abundant in the spring,
it makes sense, they become more... active.
Not surprisingly, as you move toward the equator,
spring fever disappears.
For example, scientists have noticed
that seasonal changes in the birth rates of field mice flatten out
as you get closer to the equator.
But sunshine may not be the only
springtime "pick-me-up".
For humans, the optimal temperature for good mood is 72F.
And let's face it,
once the temperature starts to rise,
we're wearing a lot less.
For Scientific American's Instant Egghead,
I'm Yasmin Tayag