Amphibians
with Tails
Salamanders are often confused
with lizards, as their sinuous profile tends to evoke
the idea of a reptile. But don't let yourself be fooled:
they are definitely a part of the surprising and numerous
family of beings with a ''double life'' - those who
live in the water and on land - reflected in the Greek-based
adjective amphibious.
There are some 300 varieties
of salamanders, but all are defined by the name of
their order: Caudata,
''with tail.'' Study of these creatures forms part
of herpetology,
which targets reptiles and amphibians, and their scientific
classification encompasses 10 different families.
The Internet is not immune to
the charm of salamanders, whose skins sport fantastic
natural designs. There are numerous directories
and links in cyberspace showing off the different
varieties: tiger-stripes, spotted, marbled, or the
common 'Salamandra salamandra,' known as the newt.
There is also a great deal of information about another
mysterious being that can be confused with a salamander:
the 'axolotl'
or the Ambystoma mexicanum.
What is the motive of this cyberspace
dedication to salamanders? Beyond the frontiers of
science, many members of the order Caudata are treasured
as pets.
Salamanders are fascinating because
of their colors, their strange shapes, and the incredible
speed with which they eat. But also because they reflect
an important part of the Earth's history.
Scientists affirm that salamanders
are descendants of the first vertebrates to come out
of the water when life was - from the perspective
of today's humans - still being formed. And the oldest
fossils of the Caudata date back 150 million years
- the middle of the Jurassic period…
Caudata:
Classification of the salamander
Newts
and salamanders
Salamanders
in Yahoo!
Photos
of salamanders
North
American Herpetology
Links
to salamander sites
How
salamanders eat
Vital
Element
Water is life. A truth so basic
that it is commonplace. Concern about the scarcity
of this ''vital element'' is widespread, as many people
believe that water will be the detonator of future
wars.
These concerns also inundate
the Internet. It is not by accident, of course. We
already know that life itself originated in water,
that water covers three-fourths of the Earth's
surface, and that 80 percent of our
bodies is simply water.
But the problem with freshwater
is perfectly easy to understand: 97.5 percent of the
water on Earth is salty, and three-fourths of the
remaining 2.5 percent are frozen around the North
and South Poles. What is left is just 0.01 percent
of this precious resource.
Even so, there is the broad impression
that this is enough to supply a very large population.
But the truth is that freshwater is not well distributed
throughout the world, and in many places it is threatened
by problems of contamination, squandering and poor
infrastructure, as occurs with the dams that affect
the basins of some major
rivers.
The standpoint of water scarcity
has generated a global mobilization, which has as
its axis the United
Nations. During the first Earth Summit, in Rio
de Janeiro in 1992, freshwater comprised an entire
chapter in the program of action known as Agenda
21. World
Water Day is now an annual event, and currently
the UN is preparing a global
report on the availability of this life-giving
resource.
UNEP:
Freshwater - Resources - Agenda 21
UNESCO:
World Water Day
Agenda
21: Chapter 18 on Water
The
world's largest rivers
24
UN agencies prepare a global report on water
A
Prodigious Crop
Corn is planted and harvested
in nearly all the Earth's farmland that is suitable
for agriculture. But it was not always so. Until 500
years ago, its use was limited to what we now know
as the Americas, from Chile to Canada.
Its global popularity began
when the first Europeans learned of its existence.
The explorers spoke of ''a kind of grain, called 'maize,'
that tastes good cooked, dried or ground into flour''.
The cultivation of this
plant, from the 'gramineae' family, originated
thousands of years ago in the area that is now Mexico
and Central America. The oldest vestiges of corn production
found in the region are some 7,000 years old. It is
here that the word ''maize'' was born, meaning ''sustenance
of life''.
Corn served as the basis of the
diet, and even the culture, of the ancient civilizations
of the Americas.
Across the Western Hemisphere,
it is known by different names: corn, maíz, choclo,
jojoto, milho, and elote, for example. There are six
basic types of corn: dentate, hard, soft (or grainy),
sweet, popcorn and sheathed.
Beyond its virtues as a food
(where it demonstrates an incredibly capacity to transform
itself into flour, pasta, etc.) maize holds other
surprises: it is used as the basic ingredient for
some industrial processes, such as the production
of starch, oil, protein, alcoholic beverages, sweeteners,
and fuels.
Reflecting its importance for
humanity, the Internet holds seemingly infinite references
to corn. There are hundreds of recipes from a wide
range of cultures, and numerous
sites that explain its uses, or inform us of its
basic characteristics.
And if you combine the word ''corn''
or ''maize'' with the term ''transgenic'' in just
about any Internet search engine, you'll enter one
of the hot debates of today: whether humanity should
be producing genetically modified corn, as the consequences
for the environment and human health are still relatively
unknown.
FAO:
Maize in Human Nutrition
The
Maize Page
Maize
Cooperation in Genetics
CornCam:
Watch Corn Grow!
Life
of a Coleopteron
Beetles inhabit nearly the entire
planet. They have one important thing in common: the
hard wing shell that gives them their armored appearance.
But beyond that, beetles are one of the most diverse
families that exist. One other thing they share is
their ''official'' name: they belong to the order
''coleoptera.''
''The beetles are the largest
order including more species known to science than
any other order not only in the Class of Insecta,
but also in the entire animal kingdom (Animalia)...
beetles constitute more than a quarter of all known
animals,'' reports a website based in St.
Petersburg.
Since ancient times beetles have
formed a part of human culture. People have studied
them and copied them in forming mythology, adornments
and even fairytales. Even old Aesop
used them in his fables.
Some beetles are famous for their
incandescent colors, others for the extraordinary
designs that adorn their wings. Some stand out
because of their strength, and others due to their
ability to survive, often for years, in the most adverse
conditions.
One Internet site affirms there
are 140 to 173 different species. Their diversity
is evident, for example, in size: there are some that
measure just 25 millimeters and others that reach
more than 10 centimeters.
Their omnipresence on Earth even
includes the Internet, where beetles are the stars
of digital
games, or simply the theme of unassuming directories.
Beetles
and coleopterists
Coleoptera
site
Aesop's
Fables: The eagle, the hare and the beetle
Digital
games, 3-D, etc.
Coleoptera,
info and photos
Beetles
illustrated
Directory
of beetle sites
The
Bug Page: Beetles
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