Growth & Evolution : Polycephaly

GROWTH AND EVOLUTION : POLYCEPHALY

One of the major focuses in Teratological studies is Polycephaly. 

Polycephaly: is a condition where an animal is born with two or more heads due to a malfunction pre-birth, the term also includes Bicephaly and Tricephaly, both referring to two-headedness. Bicephalic and Tricephalic animals are only creatures in the real world that share the same process as conjoined twins, both occurences are a result of failed separation of monozygotic twins. A variation of Polycephaly is Diprosopus, which is a condition where an animal is born with two faces on a single head. Medically, these are all classed as congenital cephalic disorders.

Each head of a polycephalic animal has it's own brain, and somehow share control of the limbs, for example, American conjoined twins Brittany and Abby Hensel say that they both have control of one side of the body, one of them left side and one of them right side. Polycephalic animals poorly in the wild compared to monocephalic animals, but most occurrences happen in captivity or in domesticated animals due to inbreeding/crossbreeding.

MAMMALS WITH REPORTED POLYCEPHALY
Many cases of polycephaly have been reported all over the world, but the following animals are more frequent than others in terms of how often cases involving the species occur:

  

Cats - Numerous reports of two-faced cats have appeared over the years being relatively common, relative to reports of other polycephalic animals, however most cases die shortly after birth.
• Cattle -most cases can be found preserved in museums around the world.
• Goats and Sheep
• Pigs
• Snakes - Most polycephalic snakes have short lives but some captive individuals can live for up to 8 years. Polycephalic snakes are usually the result of inbreeding, so these cases are most often found in zoos and pet shops rather than in the wild although it is not impossible to occur naturally. The snake heads may try to attack and even attempt to swallow each other, so feeding produces a difficult challenge for the snake.
• Turtles - Two-headed turtles and tortoises are rare but not unheard of.
• Crocodiles

Growth & Evolution : Teratology

GROWTH AND EVOLUTION : TERATOLOGY

From the previous list of specific types of growth, I have identified Teratology to be the most interesting to me and also the most unusual and unseen in terms of being thoroughly explored by artists. There are no artists that I could discover who have based their work solely on teratology, it's sub-genres or related topics, so I thought this would be the perfect thing to investigate due to it not have been done extensively before. Throughout my research I will present images involving teratology, and related subjects, that will inspire my work and analyse how the artist has depicted growth and evolution in their artwork. 


Teratology: The study of congenital abnormalities of physiological development and formation. Or put into a simplified definition, Teratology is the study of abnormalities and defects found on plants and animals, such as extra limbs or organs. Most people mistakenly think that teratology is just the study of human congenital abnormalities, yet it is broad and as previously said it also studies abnormalities of plants and animals (all non-human forms that these abnormalities can affect). The kind of abnormalities that teratology investigates include Polycephaly, Conjoining, Supernumerary Body Parts, Chimeras and Hybrids.What can cause these abnormalities?

• Toxic substances: eg drugs, alcohol, nicotine intake during pregnancy, or exposure to environmental toxins.
• Vertically transmitted infection: infections or viruses transmitted directly from mother to embryo during developing stages in the womb which can alter or interrupt the growing/formation process.
• Lack of nutrients: eg lack of folic acid intake for mothers during a human pregnancy increases the risk of the baby developing Spina Bifida.)
• Physical restraint.
• Genetic disorders passed down through the genes.

One notable point about such abnormalities is that they are not only recent occurrences. There is evidence of congenital deformity in fossils that have been found, which prove scientifically significant allowing scientists to delve into evolutionary history of life's development processes. This shows scientists that congenital disorders have remained similar since the most recent common ancestor of dinosaurs and mammals. Examples include:

-T-rex fossil with block vertebra in it's spine, similar modern cases occur in human spines.

-A specimen of a deformed Hyphalosaurus with two heads, the earliest case of Polycephaly, dating back to 120 million years ago.

The next step of my research will be looking at the condition of Polycephaly, one of the most intriguing cases of congenital disorders and malfunctions in growth.

Growth & Evolution initial thoughts.

GROWTH & EVOLUTION

This begins the preparation for my final major project, the last project I will complete before the end of my time at college, and the theme I have been given is Growth & Evolution. My aims are to independently investigate the unusual and possibly un-thought of side of this topic, choosing challenging and interesting  paths of investigation in such a broad and diverse subject. I plan on experimenting with a wide range of mediums, materials and methods of creating inspiring and thought-provoking art. I also plan on creating in-depth analysis of artists' work and a detailed look into how artists have depicted growth and evolution throughout modern history.

Evolution has a varied selection of definitions, some being:

• A gradual process in which something changes into a different and usually more complex (or better) form.
• A pattern formed by a series of movements.
• A process of gradual, progressive change and development, eg within a social or economic structure.
• A process of development and change from one state to another, as of the universe in it's development through time.

Growth:

• An increase, as in size, number, value, or strength; extension or expansion.
• Development from a simple to a complex stage.

From a list I found of specific types of growth I have narrowed it down to the following feel that I am interested by. One of these will be the starting point of my further research:

• Chemotropism: Growth or motion in response to chemical stimulus.
• Endogeny: Development or growth from within.
• Epibony: The growth of part of an organism in such a way that it overlays or surrounds another.
• Stereotropism: Growth or movement determined by contact with a solid.
• Teratology: The study of malformations or abnormal growth in animals or vegetables.