Wednesday, January 18, 2012

Insect: A Sex On Six Legs



Greatest number: The animal kingdom's working class they are, constituting 90 percent of all the species found on our planet, while including invertebrates they form 99 percent of life forms on earth. Insects are the life-forms most adapted, socially most advance, even their sexes are determined based on their working nature in their society.

Ecological importance: The sheer magnitude of insect numbers mean that they could not be eliminated without leaving a hole so large ... that the rest of the world's organisms would be unable to continue their lives.

The caste system
:
The caste system of insects enables eusociality the division of labor between non-breeding and breeding individuals. A series of polyphenisms determines whether larva develop into queen, workers and in some cases soldiers. In some ants, an embryo must develop under certain temperature & photoperiod conditions in order to become a reproductively-active queen. In bees, royal jelly provided by worker bee causes a developing larva to become a queen. Royal jelly is only produced when the queen is aging or has died.

Polyphenism: A polyphenic trait is a trait for which multiple, discrete phenotypes can arise from a single genotype as a result of differing environmental conditions.

Key of the caste
:
When a queen lays eggs, each egg can develop into a different caste depending on the environment it is in -- the temperature it develops at and the nutrition it receives. But the key to "switching" into a specific caste is controlled to a large extent by one chemical inside the eggs, which is called juvenile hormones.

Scientist believes this as unleashing of some kind of ancestral potential. That reveals the hidden evolutionary potential.


Giant super soldiers in lab
:
(ref: BBC, Nature News, 5 Jan 2012) Dr. Ehab Abouheif from McGill University in Montreal led the team which found that treating ant larvae with a hormone at a very specific time during their development turned those ants into the giant super soldiers.

More possible implication of this finding
:
Dr. Abouheif says that the unlocking desirable ancestral features could be key to breeding crop plants with higher nutritional value or even tracking the mechanism that causes cancer. "Who's to say that all of that crazy growth that occurs in cancer isn't the unleashing of some kind of ancestral potential," he said. "If we could find what that was, may be we could reverse it", reveals that hidden trait could be unlocked in many species.

Sunday, January 15, 2012

Survivors Of The Future

The largest animal group: Arthropods are animals with segmented bodies and six or more jointed legs. They are the largest animal group on Earth. In fact, more than three out of four of all animals are arthropods. They are found everywhere - on land, in trees, in freshwater and saltwater, and even underground. Arthropods are generally small. Most are less than 1 cm long. Some arthropods, however, are quite large. The giant king crab, for example, measures over 3.2 m from the tip of one outstretched leg to another. Some of the most familiar arthropods are butterflies, beetles, flies, ants, bees, spiders, scorpions, shrimp, and crabs.

The arthropods constitute over 90 percent of the animal kingdom.


The earliest guest of our planet:
Arthropods provide the earliest identifiable fossils of land animals, from about 419 million years ago in the Late Silurian, and terrestrial tracks from about 450 million years ago appear to have been made by arthropods.[49] Arthropods were well pre-adapted to colonize land, because their existing jointed exoskeletons provided protection against desiccation, support against gravity and a means of locomotion that was not dependent on water.[50] Around the same time the aquatic, scorpion-like eurypterids became the largest ever arthropods, some as long as 2.5 metres (8.2 ft).

Future belongs to them: Their track record strongly recommends that in future they certainly will evolve with more adaptations to the changing scenario on our planet, while humans and other animal species have a weak chance to survive. May be they rule the world with greater sizes and with adaptations unknown and unimaginable so far.

Insects and grasses: It's hard to imagine that if we humans misuse our nuclear war potential, who will survive on this blue planet except Insects and Grasses (as grasses too have special tissue structures which makes them a better contender for survival than the Dicot plants) !!



Saturday, January 14, 2012

Biological Classification: Kingdom Animalia















Origin of life
: Even the oldest human observation (like the Rig Vedic period of India) recorded in history, supports the thought that most primordial life forms might have began in water only.
(reference: pictures 1, 2 & 3 of a hymn from Rig Veda shown are in old Sanskrit language text translated in Hindi & English).


Later Miller-Urey experiment (1952-53) and Oparin proved it so in laboratory conditions for the modern mind.
Primordial Soup: This first life form, sort of naked protoplasm kind of thing took the shape, which was named Cell by Robert Hooke (1665) and life began to grow and took a route of simple to complex forms, towards two major branches, as animal and plant cell.
(reference: picture 4, 5 & 6).

Need of Classification: As number of life forms were in millions with much variety, a need arose to name and classify them. As we all know the credit goes to Carolus Linnæus a Swedish botanist, physician, and zoologist, father of modern taxonomy. Credit for Binomial nomenclature also goes to
Linnæus. The application of binomial nomenclature is now governed by various internationally agreed codes of rules, of which the two most important are the International Code of Zoological Nomenclature (ICZN) for animals and the International Code of Botanical Nomenclature (ICBN) for plants.
(reference picture: 7, 8 & 9)

System of Classification and their Units: All the types of classifications proposed & followed from Linnaeus (1735) to Cavalier-Smith (2004) follow almost the same domain name of units as: Kingdom-Phylum-Class-Order-Family-Genus-Species.
(reference picture: 11, 12 & 13)

Interesting Evolutionary Trend: The classification patterns followed is so interesting that this itself is an Evidence in the support of Darwin's theory of Organic Evolution.
As we move from base of the classification, we find the life forms they them self are arranged in simpler to complex forms like:
Unicellular Prokaryote-Unicellular Eukaryote- Multicellular Tissue level- Multicellular organ level- Multicellular Organ System level.
(reference picture: 14)


Pineal gland, the mystical third eye

Pineal gland   It is a very small unpaired midline brain structure of endocrine gland, tiny as a rice grain size, situated laterally (anatom...