History of Biology

Biology is the study of life on earth. The History of Biology however, focuses on the advent of life on earth, right from the ancient times. Biological discoveries have a remarkable impact on the human society. Traditionally, the history of biology is diversified into two wings – studies on medicine and theories of natural history. Medicines are not results of current biological discoveries.

Have you heard names like Hippocrates, Aristotle and Galen of Pergamum? Well, these eminent people were first explorers of the anatomy and physiology of living organisms. Their works focused on the naturalist leanings of organisms, especially animals. Theophrastus, the most notable work of Aristotle still holds a valuable place in the hearts of our modern-day scientists. Do you know why? Theophrastus makes an enormous contribution to the study of zoology, botany, ecology and taxonomy, all of which are essential branches of biology.

Awareness about medicines became prominent during the middle ages. It is believed that Islamic scholars working in accordance with the Galenic and Aristotelian traditions were the first to introduce medicinal science. Neolithic was a big turning point in the history of biology. This age-old revolution dated 10,000 years ago brought practices of farming and animal husbandry into limelight. Much before the study of human beings, biology referred to the study of plant and animal life. Works on botanical studies by Albertus Magnus (1206-1280) and ‘The Art on Falconry,’ introducing the first resource to ornithology by the Holy Roman Emperor Frederick II (1194-1250) played a pivotal role in shaping the natural history of biology.

Botany flourished during the Renaissance and early modern period. Plants were then referred as ‘materia medica’ because studies proved that plants brimmed with amazing medicinal properties. Not just the Greek culture but ancient cultures of Egypt, China, Mesopotamia and India had immense contribution in the evolution of biology. From classical Chinese medicine, formulated on the basis of theories by Yin and Yang and the Five Phases to the Indian introduction of Ayurveda, discovery and study of medicinal sciences became highly popular. Zhuangzi, the noted Taoist philosopher first brought his ideas about evolution on the boards during the 4th Century. His philosophy stated that species differ in attributes in response to diverse environmental conditions. Developments began springing in gradually during the 17th and 18th Century. Theories regarding a quantitative approach to physiology and Santorio’s studies on Metabolism ruled the charts. It was only during the 19th Century whenseveral disciplines of biological science were introduced like embryology, cytology, morphology, bacteriology, paleontology, geography and geology.

The roots of Biology, the term coined after combining the Greek words of ‘Bios’ meaning lifeand ‘Logy’ meaning science dates back to the secular traditions of ancient philosophies. Learning about the history of biology is an attempt to understand the evolution of science

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THEORIES OF LIFE

1. Theory of Special Creation

According to this theory, all the different forms of life that occur today on planet earth, have

been created by God, the almighty. Adam and Eve were, according to the Book of Genesis, Bible

and Quran the first man and woman created by the God. Life on earth began from them

according to Christians, Muslims and Jews. The 3 religions have a common agreement on the

fact God created the universe in seven days, reserving for his sixth-day labor the climax of

creation: man and woman. On the seventh day God rests and so establishes the holiness of the

Sabbath. God fashioned a man form the dust and blows the breath of life into his nostrils, then

planted a garden (the Garden of Eden) and caused to grow in the middle of the garden the Tree

of Knowledge of Good and Evil and the Tree of Life. God set the man in the garden “to work it

and watch over it,” permitting him to eat from all the trees in the garden except the Tree of

Knowledge, “for on the day you eat of it you shall surely die.” God brought the animals to the

man for him to name. None of them was found to be a suitable companion for the man, so God

caused the man to sleep and created a woman from a part of his body (Tradition describes the

part as a rib). The Quran says that Adam initiated the fruit eating and that both Adam and Eve

(Hawa) ate the forbidden fruit, for which God later forgave them, and then sent both of them

down to earth as his representatives. The Hadith (the prophetic narrations) and literature shed

light on the Muslim view of the first couple. The concept of original sin does not exist in Islam,

as Adam and Eve were forgiven after they repented on Earth, according to the Quran. One of the

differences between the Qur’an and the book of Genesis is that it does not recount the Genesis

narrative in which Eve leads Adam to transgress God’s laws; they are simply both held

responsible and thus sent to earth.

2. Organic Evolution

Speciation stretches back over 3.5 billion years during which life has existed on earth.  It is

thought to occur in multiple ways such as slowly, steadily and gradually over time or rapidly

from one long static state to another. Evolution (also known as biological or organic evolution) is

the change over time in one or more inherited traits found in populations of organisms. Inherited

traits are particular distinguishing characteristics, including anatomical, biochemical or

behavioural characteristics, that are passed on from one generation to the next. Evolution has led

to the diversification of all living organisms, which are described by Charles Darwin as “endless

forms most beautiful and most wonderful”.

3. Materialistic Theory

According this theory, the origin of life on earth is the result of a slow and gradual process of

chemical evolution that probably occurred about 3.8 billion years ago. Chemical evolution refers

to molecular evolution is the process of evolution at the scale of DNA, RNA, and proteins.

Molecular evolution emerged as a scientific field in the 1960s as researchers from molecular

biology, evolutionary biology and population genetics sought to understand recent discoveries on

the structure and function of nucleic acids and protein. Some of the key topics that spurred

development of the field have been the evolution of enzyme function, the use of nucleic acid

divergence as a “molecular clock” to study species divergence, and the origin of noncoding

DNA.

4. Theory of Consecutive Creations

The idea of extinction paved the way for the theory of catastrophism or “consecutive creations”,

one of the predecessors of the evolution theory. Catastrophism is the idea that Earth has been

affected in the past by sudden, short-lived, violent events, possibly worldwide in scope. This

view holds that the present is the key to the past, and that all things continue as they were from

the beginning of the world. According to this theory, since each catastrophe completely

destroyed the existing life, each new creation consisted of life form different from that of

previous ones. French scientists Georges Cuvier (1769-1832) and Orbigney (1802 to 1837) were

the main supporters of this theory.

 

5. Clay Theory

A model for the origin of life based on clay was forwarded by A. Graham Cairns-Smith of the

University of Glasgow in 1985 and explored as a plausible illustration by several other scientists,

including Richard Dawkins. Clay theory postulates that complex organic molecules arose

gradually on a pre-existing, non-organic replication platform—silicate crystals in solution.

Complexity in companion molecules developed as a function of selection pressures on types of

clay crystal is then exapted to serve the replication of organic molecules independently of their

silicate “launch stage”.

6. Spontaneous Generation

Until the early 19th century, people generally believed in the ongoing spontaneous generation of

certain forms of life from non-living matter. This was paired with the belief in heterogenesis, e.g.

that one form of life derived from a different form (e.g. bees from flowers). Classical notions of

spontaneous generation, held that certain complex, living organisms are generated by decaying

organic substances. According to Aristotle it was a readily observable truth that aphids arise

from the dew which falls on plants, flies from putrid matter, mice from dirty hay, crocodiles

from rotting logs at the bottom of bodies of water, and so on. Spontaneous generation or

Equivocal generation is considered obsolete by many, regarding the origin of life from inanimate

matter, which held that this process was a commonplace and everyday occurrence, as

distinguished from univocal generation, or reproduction from parent(s). The theory was

synthesized by Aristotle, who compiled and expanded the work of prior natural philosophers and

the various ancient explanations of the appearance of organisms; it held sway for two millennia.

It is generally accepted to have been ultimately disproven in the 19th Century by the experiments

of Louis Pasteur. The disproof of ongoing spontaneous generation is no longer controversial,

now that the life cycles of various life forms have been well documented. However, the question

of biopoesis or abiogenesis, how living things originally arose from non-living material, remains

relevant today

7. Endosymbiosis

The endosymbiotic theory was first articulated by the Russian botanist Konstantin

Mereschkowski in 1905. According to this theory, certain organelles originated as free-living

bacteria that were taken inside another cell as endosymbionts. Mitochondria developed from

proteobacteria (in particular, Rickettsiales or close relatives) and chloroplasts from

cyanobacteria. It suggests that multiple forms of bacteria entered into symbiotic relationship to

form the eukaryotic cell. The horizontal transfer of genetic material between bacteria promotes

such symbiotic relationships, and thus many separate organisms may have contributed to

building what has been recognised as the Last Universal Common Ancestor (LUCA) of modern

organisms.

 8. Cosmogeny

Cosmogeny, is any theory concerning the coming into existence or origin of the universe, or

about how reality came to be. In the specialized context of space science and astronomy, the term

refers to theories of creation of (and study of) the Solar System. Attempts to create a naturalistic

cosmogony are subject to two separate limitations. One is based in the philosophy of science and

the epistemological constraints of science itself, especially with regards to whether scientific

inquiry can ask questions of “why” the universe exists. Another more pragmatic problem is that

there is no physical model that can explain the earliest moments of the universe’s existence  

because of a lack of a testable theory of quantum gravity, although string theorists and

researchers in loop quantum cosmology believe they have the formulas to describe it within their

field equations.

9. Biopoesis

In natural science, abiogenesis or biopoesis is the study of how biological life arises from

inorganic matter through natural processes, and the method by which life on Earth arose. Most

amino acids, often called “the building blocks of life”, can form via natural chemical reactions

unrelated to life, as demonstrated in the Miller–Urey experiment and similar experiments that

involved simulating some of the conditions of the early Earth in a laboratory. In all living things,

these amino acids are organized into proteins, and the construction of these proteins is mediated

by nucleic acids, that are themselves synthesized through biochemical pathways catalysed by

proteins. Which of these organic molecules first arose and how they formed the first life is the

focus of abiogenesis.

10. Panspermia

Panspermia is the hypothesis that life exists throughout the Universe, distributed by meteoroids,

asteroids and planetoids. Panspermia proposes that life that can survive the effects of space, such

as extremophile bacteria, become trapped in debris that is ejected into space after collisions

between planets that harbor life and Small Solar System Bodies (SSSB). Bacteria may travel

dormant for an extended amount of time before colliding randomly with other planets or

intermingling with protoplanetary disks. If met with ideal conditions on a new planets’ surfaces,

the bacteria become active and the process of evolution begins.

Recent probes inside comets show it is overwhelmingly likely that life began in space, according

to a new paper by Cardiff University scientists.

References:

- http://www.bioexplorer.net/history_of_biology/

-http://www.smashinglists.com/top-10-theories-on-beginning-of-life-on-earth/