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Re: attack on dinosaur--horrific video
john bois writes:
many would-be predators don't like getting wet
The eggs are not laid in water.
They are laid in swamps--many nests are accessible only by getting one's
predatory threat can only come from 180 degrees not 360;
No, croc nests are not directly next to the water.
But a croc only has to scan 180 degrees--predators are not going to be
accessing the nest from the water. And to do this a croc can lie as still
as a log waiting to ambush. This is an exceptionally effective strategy
whether animals are merely trying to get a drink of water or robbing a
In areas prone to flooding, croc nests are often on ground high enough to
prevent the nest being inundated. In those cases a land-based attack on the
nest can come from any direction. Many a croc has lost a few eggs to hungry
varanids that sneak up behind the mother and quietly dig into the mound.
It's unlikely that every single egg layed will be dug up and eaten though.
Even if a nest mound is right next to the water (or on an island in a
swamp), a varanid will happily take a swim to get to it - as will just about
any other predator that habitually robs croc nests (since they're living in
the same swampy area to begin with).
The real benefit of a protective mother comes after the eggs hatch, when the
hatchlings are wiggling about above ground (or in the water) for all to see.
The act of burying the eggs is probably a better defence than actively
guarding the nest, provided the number of eggs layed is large enough to
offset predation (ask any marine turtle...) In fact, the presence of a
nest-guarding mother probably *attracks* nest raiders. If you're a marine
turtle that moves slowly on land and has no really effective means of
attack, then guarding the nest is pointless. However if you're a large
voracious carnivore that can move quickly and has a killer set of teeth,
then the effectiveness of guarding the nest probably outweighs the fact that
a guardian mother is a living billboard advertising a nest's location.
GIS / Archaeologist geo cities.com/dannsdinosaurs
Melbourne, Australia heretichides.soffiles.com