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Notis: Det följande är en reproduktion av artiklen
"Reptiles II: Turtles."
Generally in nature, an animal must seek shelter from bad weather or from
a threatening situation. Imagine a creature carrying its shelter or its house
with it wherever it goes. When threatened, it simply retreats into its house
and locks the door. That's essentially how turtles live their lives. The
turtle's shell is a remarkable feat of natural engineering, a protective
gift from God. The shell has two parts?the carapace, the upper section and
the flat belly section called plastron. They are connected by bony bridges
leaving gaps for the head, tail and four legs. The tur-tle's vertebrae and
ribs have actually become an integral part of the carapace and do not move
separate from the shell. When the turtle withdraws into this shell, it's
almost impossible for a predator to get at it.
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The shell accounts for about one
third of the weight of a turtle, yet most turtles are agile, strong walkers
or swimmers and many climb with great ease. They have developed strong legs,
especially in giant species, like the Galapagos tortoise which travels great
distances, although slowly. They could carry the weight of a man on their
back and keep right on going. The tortoise travels about 4 miles a day. On
the other hand, sea turtles have devel-oped flipperlike legs and sleek shells.
They swim at about 20 miles an hour. The distance a sea turtle might travel
in one hour would take a week for a tortoise to cover.
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Turtles are ancient life forms. The earliest fossils recognized as turtles
date from the Triassic period, about 200 million years ago. Turtles were
in existence prior to the emergence of the great dinosaur groups and survived
the demise of the dinosaurs, continuing to adapt and flourish. Turtles occupy
almost every imaginable habitat-woods, ponds, rivers, lakes, marshlands,
prairies, deserts and the open ocean, and they eat food as varied as insects,
tender seagrasses, carrion, fruit and fish.
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Turtles have great similarity yet
great variation as well. The Galapagos tortoise evolved on islands with no
predators and little competition. They grow very large-500-600 pounds-and
live 100-150 years. Desert tortoises are much smaller. They eat cactus fruit
and desert grasses and because of their environment, God has given them
adaptations to be able to survive without water. They get the moisture they
need from the food they eat. The pancake tortoise of Africa has a flat, soft shell, instead of the hard
dome common to most turtles. It looks sort of like someone dropped a frying
pan on him. This allows him to easily climb rocks and lie under them. When
threatened, he will wedge himself into a rocky crevice and then inflate his
body so he's almost impossible to pull out.
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The red toad-headed turtle with its brilliant red head is an example of the
variation in bright and beautiful colors. Various beautiful design patterns
on the shell show God's wondrous creation. These include map turtles, so
named because of the intricate patterns of yellow lines that actually look
like lines on a topo map; the radiated tortoise of Madagascar has yellow
circles with lines radiated out from them; and the leopard tortoise of Africa
whose shell is covered with distinctive and beautiful yellow spots.
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One fascinating turtle species is
the alligator snapping turtle, which may grow to 200 pounds. He lives on
muddy river bottoms, sitting quietly with his brown shell blending with the
mud. He keeps his mouth open and wiggles his tongue which is a bright pink.
Like a lure, this attracts fish which swim right in and the turtle simply
snaps its mouth shut. They may move no more than a few feet their whole lives.
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Tortoises live almost exclusively on land. Many turtles move between land
and water. Sea turtles spend virtually their whole life in water. The female
comes out to lay eggs and she will return to the very beach where she was
hatched. The whole process is truly amazing. She comes on shore, usually
at night, and digs a nest into which she lays up to 100 eggs. She buries
the eggs and leaves. As the embryo grows into a fully developed hatchling,
the shell that has offered nourishment and protection becomes a kind of prison
from which the baby turtle must escape. God has provided an "egg tooth,"
actually a horny projection located on the tip of the snout (which disappears
as the turtle grows). The tiny hatchling uses it to pierce its shell, then
pulls it apart with his forelimbs. All eggs in a nest hatch at virtually
the same time and they use that community spirit in order to escape from
the nest. Experiments with single eggs show that few break free on their
own. Together the baby turtles scrape down the walls and ceiling of the nest
and instinctively climb upward till they break free.
Then these hatchlings, only a couple of inches long, know that they must
scramble for safety, perhaps a hundred yards or more across the open beach
to the sea. And it's not just the hundred-yard dash that's difficult; predators
of all kinds are waiting-birds, dogs, skunks and others seem adept at knowing
where nests are and when they will hatch. Only a fraction make it to the
sea and even then they are easy pickings for large fish and sea gulls.
Little is known of the first year of wild hatchlings. They simply disappear
from sight, going weeks without food if necessary and struggling to escape
predators of all kinds. Those that survive to adulthood will spend their
lives, perhaps 50 years, swimming around in the open ocean. The male turtles may never leave the ocean their whole life; the female only
to lay eggs. We do not understand how turtles, migrating over great stretches
of open ocean, find their way around. How does the female green turtle find
her way back to the beach where she was hatched decades before? "The feat
of locating Ascension Island, barely seven miles across, after negotiating
1400 miles of open ocean, by an animal that is hopelessly myopic when it
raises its eyes above the level of the water, seems little short of miraculous."
And it is miraculous, God's miracle.
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One marine turtle, the Kemp's ridley,
the smallest, rarest and most endangered of all sea turtles, has unusual
nesting behavior. Unlike most sea turtles which nest individually, the Kemp's
ridley all come to the same location, a remote beach in Mexico, gather offshore
and then swarm onto the beach together-perhaps 40,000 strong. Until the 1940's
this event, known locally as "arribada", was a well-kept secret. Natives
used it as a way to obtain meat and eggs. Once it became common knowledge
the turtles were exploited nearly to extinction. Today the Mexican gov-ernment
patrols the beaches with armed guards during arribada, but in recent years
only about 400 females come ashore to nest each season, one percent of the
number just 50 years ago.
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Turtles through myth and legend were generally regarded as symbols of strength,
stability, benevolence and wis-dom. We generally like turtles, unlike most
reptiles. Yet, we kill them for their shells and take away their habitats,
leave many species on the brink of extinction. We need to appreciate these
creatures of God, remembering Verse 11:6 There is not a creature on earth
whose provision is not guaranteed by God. And He knows its course and its
final destiny. All are recorded in a profound record.
Among His proofs is the creation of the heavens and the earth, and the creatures
He spreads in them. He is able to summon them, when He wills. (42:29)
Lydia Kelley
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