by Licia Johnson, Naturalist
I have recently been creating new programs for our
curriculum at the Discovery Center.
Researching and reading on different animals in the Northwoods has
really taught me a lot, but something that I have really noticed are just how
incredible some body parts of certain animals really are. Nothing has stood out to me more the tongue. Humans use tongues to aid in eating, tasting
and speaking, and I was amazed at the different ways that animals have adapted
to use theirs.
Snakes
If you have ever watched a snake slithering around exploring
its environment, you have inevitably watched as it quickly sticks out its
tongue. There is a very important
function going on with this simple motion.
IF you take a close look at the tongue of a snake, you will notice that
it is forked at the end. When a snake is
flicking its tongue out, it is smelling and sensing its surroundings by
collecting particles in the air. What we
can’t see, is when the snake brings its tongue back into its mouth, it sticks
the forked end into two holes in the pallet of the mouth known as the
Jacobson’s Organ. This organ allows the
brain to perceive and detect prey. The
snake does not use its tongue for tasting or as an aid when eating.
Butterflies
Butterflies have a specially adapted mouthpiece known as a
proboscis. If you have ever watched an
adult butterfly land on a flower, you may have noticed that a small straw-like
body part unravels out of the mouth area and stick into the center of the
flower. Unlike their caterpillar
metamorphic stage, who eats with a chewing mandible mouthpiece, adult
butterflies must ‘suck’ up their food.
They have adapted to have a long, tongue-like mouthpiece that does
exactly that. The proboscis is actually
made up of two separate pieces, long grooved half-tubes that are separate when
the adult emerges from the chrysalis.
They are then unrolled and rolled up until they are literally ‘zipped’
together, forming a tube. Included in
this tube are several muscles and a trachea.
As a butterfly flies around and lands on flowers, the proboscis is unrolled
and stuck into the flower. It was once believed that they suck up nectar like a
straw, but some studies show that butterflies bring up the nectar using
capillary action- just like water moves across paper towel.
Hummingbirds
When a hummingbird hovers around a flower to collect nectar,
it sticks an almost translucent tongue into a flower. It was once believed that the tongue worked
like a straw, but hummingbirds don’t suck up nectar, they lick it up. The tip of their tongue is forked and has a
hollow trough. Nectar is drawn into
these troughs through capillary action, similar to the butterfly. As the bird
extends its tongue again and again for each lick, this brings a pulsing stream
of nectar into its mouth.
Woodpeckers
We are familiar with the rat-a-tat-tat-tat-tat sound of the
woodpecker resonating throughout the northern forests. Woodpeckers drill holes in trees for many
reasons, to create nesting cavities, in a courtship ritual, and in search of
food. While searching for insects to
consume, woodpeckers will drill holes into the trees, listen for bug activity,
and continue until a cavity is created that they can stick their bills
into. This is when the amazing
woodpecker tongue goes to work. Inside
the trees are incredible networks of tunnels created by numerous species of
insects. The woodpecker hole literally
‘taps’ into these networks in search of food.
Once the bill is located inside the cavity, a long, sticky tongue comes
out and probes around the tunnels to catch the meal. The tongue of a woodpecker needs to be quite
long in order to achieve this, sometimes reaching three times the length of the
bill! The tip of a woodpecker tongue is
hard and pointed with barbs (similar to a porcupine’s quill). The pointed end pierces through the insect,
the barbs keep the insect on the tongue, and it is brought back into the mouth
of the woodpecker. This long tongue
finds its start at the base of the right nostril, extends around the head, and
out the mouth. It’s important to note
that not all woodpeckers have this adaptation, Northern flickers, who often
feed on the ground, have long, smooth, sticky tongues with which they probe
anthills. Yellow-bellied sap suckers
have a shorter tongue with feathery bristles that help it lap up the sap from
holes it creates in trees.
