I remember getting an e-mail a few years back regarding a man-eating python!
Besides that, there have been so many other stories about and photos showing
snakes swallowing their unfortunate human victims, whole —THIS IS NOT FOR THE
FAINT-HEARTED! There have been
contentions as to whether snakes can really stuff food the size of the average
man through their mouths but doesn’t that just make you wonder how big a
snake’s jaw can expand to accommodate their feeding behaviour?
A king cobra with head raised
Photograph
by Mattias Klum (Image retrieved from http://www.nationalgeographic.com/index.html)
I have to admit that I am extremely terrified of snakes. In
spite of that I have always wondered how snakes swallow the animals they prey
on whole, without having to chew them first. Even relatively smaller snakes
like cobras do not chew their prey as they will just gulp the poor mouse down
their ‘throats’. So I looked up National Geographic to check out some videos on
these remarkable feats. It
is really amazing!
There are generally two kinds of snakes—venomous
and non-venomous. The former depend on their venomous fangs to immobilize
their prey before feeding on them. The neurotoxins that are transferred
into the bloodstreams of the prey paralyses them which would then facilitate
these snakes to swallow the prey without any struggle from the latter. Venomous
snakes include black mambas and cobras.
Close-up of a Black Mamba
Photograph by George Crall
(Image retrieved from http://www.nationalgeographic.com/index.html)
The non-venomous snakes on the
other hand are usually bigger in size and they too immobilize their prey before
they feed on the latter. However, this is through coiling around the victim,
thus crushing the animals to death before swallowing them whole (like the
anaconda in the previous National Geographic video), just like their venomous
counterparts. Snakes like pythons and anacondas are usually bigger and stronger
to enable them to wrest their victims still. However the most intriguing things
here are how these snakes expand their jaws to a size comparable to that of
their food.
Image retrieved from whiteafrican.com
Snakes’ jaws are unlike that of human beings whose upper jaw
is “fused to the skull and therefore unable to move”. Snakes have jaws that are
relatively more ‘mobile’ that are able to move both front-to-back and
side-to-side. The bones connecting the upper and lower jaws of snakes work like
‘hinges’, thus allowing the lower jaw to “dislocate” and the mouth to gape. On
top of that, the sides of the jaws of snakes are not fused together in the
middle like our chins. Instead their ‘chins’ are made up of muscular tissues
which facilitate the expansion of their jaws way beyond the initial size of
their mouths. Read more about this and venomous fangs here.
(Diagram retrieved from
How Snakes Work)
For a thorough scientific explanation on the mechanisms of
the jaws of snakes, you can take a look at this research paper on the “Kinesis
of the Jaw Apparatus during Swallowing in Cottonmouth Snake, Agkistrodon piscivorus” in JSTOR.
Not only do their jaws expand during feeding, but so do
their hearts!
However, although it has been thought by all experts that
all snakes swallow their prey whole, as was my initial perception; but recently
it has been found that there is a kind of snake that eats “bite
by bite”. More interestingly these snakes are found in Singapore!
References
- “Ular
Sawa Telan Manusia (Python Swallows Human)”
by ‘sirloin skipper’. Fotopages, 10th November 2006.
- “Man Eating
Python”. Black Bear Heaven.
- “Different
Types of Snakes” by Roy D’Silva. Buzzle.com, 5th May 2007.
- “How Snakes Work” by
Lacy Perry. How Stuff Works: It’s good to know.
- “Pythons
Grow Bigger Hearst at Mealtimes” by James Owen. National Geographic
News, 2nd March 2005.
- “Kinesis of the Jaw Apparatus during Swallowing in
Cottonmouth Snake, Agkistrodon
piscivorus” by Kenneth V. Kardong. JSTOR, 1977(2):
338-348.
- "Snake eats its prey bite by bite". CNN.com/Sci-Tech, 10th July 2002.