Zoology (/zuːˈɒlədʒi, zoʊˈɒlədʒi/) or animal biology is the
branch of biology that studies the animal kingdom, including the
structure, embryology, evolution, classification, habits, and
distribution of all animals, both living and extinct, and how they
interact with their ecosystems. The term is derived from
ζῷον, zōion, i.e. "animal" and λόγος, logos, i.e.
Ancient history to Darwin
3 Branches of zoology
4 See also
6 External links
Ancient history to Darwin
Conrad Gesner (1516–1565). His Historiae animalium is considered the
beginning of modern zoology.
Main article: History of zoology (through 1859)
The history of zoology traces the study of the animal kingdom from
ancient to modern times. Although the concept of zoology as a single
coherent field arose much later, the zoological sciences emerged from
natural history reaching back to the biological works of Aristotle and
Galen in the ancient Greco-Roman world. This ancient work was further
developed in the Middle Ages by Muslim physicians and scholars such as
Albertus Magnus. During the
Renaissance and early modern
period, zoological thought was revolutionized in Europe by a renewed
interest in empiricism and the discovery of many novel organisms.
Prominent in this movement were
Vesalius and William Harvey, who used
experimentation and careful observation in physiology, and naturalists
such as Carl Linnaeus, Jean-Baptiste Lamarck, and Buffon who began to
classify the diversity of life and the fossil record, as well as the
development and behavior of organisms.
Microscopy revealed the
previously unknown world of microorganisms, laying the groundwork for
cell theory. The growing importance of natural theology, partly a
response to the rise of mechanical philosophy, encouraged the growth
of natural history (although it entrenched the argument from design).
Over the 18th and 19th centuries, zoology became an increasingly
professional scientific discipline. Explorer-naturalists such as
Alexander von Humboldt
Alexander von Humboldt investigated the interaction between organisms
and their environment, and the ways this relationship depends on
geography, laying the foundations for biogeography, ecology and
ethology. Naturalists began to reject essentialism and consider the
importance of extinction and the mutability of species. Cell theory
provided a new perspective on the fundamental basis of life.
Main article: History of zoology (since 1859)
These developments, as well as the results from embryology and
paleontology, were synthesized in Charles Darwin's theory of evolution
by natural selection. In 1859, Darwin placed the theory of organic
evolution on a new footing, by his discovery of a process by which
organic evolution can occur, and provided observational evidence that
it had done so.
Darwin gave a new direction to morphology and physiology, by uniting
them in a common biological theory: the theory of organic evolution.
The result was a reconstruction of the classification of animals upon
a genealogical basis, fresh investigation of the development of
animals, and early attempts to determine their genetic relationships.
The end of the 19th century saw the fall of spontaneous generation and
the rise of the germ theory of disease, though the mechanism of
inheritance remained a mystery. In the early 20th century, the
rediscovery of Mendel's work led to the rapid development of genetics,
and by the 1930s the combination of population genetics and natural
selection in the modern synthesis created evolutionary biology.
Cell biology studies the structural and physiological properties of
cells, including their behavior, interactions, and environment. This
is done on both the microscopic and molecular levels, for
single-celled organisms such as bacteria as well as the specialized
cells in multicellular organisms such as humans. Understanding the
structure and function of cells is fundamental to all of the
biological sciences. The similarities and differences between cell
types are particularly relevant to molecular biology.
Anatomy considers the forms of macroscopic structures such as organs
and organ systems. It focuses on how organs and organ systems work
together in the bodies of humans and animals, in addition to how they
Anatomy and cell biology are two studies that are
closely related, and can be categorized under "structural" studies.
Animal anatomical engraving from Handbuch der Anatomie der Tiere für
Physiology studies the mechanical, physical, and biochemical processes
of living organisms by attempting to understand how all of the
structures function as a whole. The theme of "structure to function"
is central to biology. Physiological studies have traditionally been
divided into plant physiology and animal physiology, but some
principles of physiology are universal, no matter what particular
organism is being studied. For example, what is learned about the
physiology of yeast cells can also apply to human cells. The field of
animal physiology extends the tools and methods of human physiology to
Physiology studies how for example nervous, immune,
endocrine, respiratory, and circulatory systems, function and
Evolutionary research is concerned with the origin and descent of
species, as well as their change over time, and includes scientists
from many taxonomically oriented disciplines. For example, it
generally involves scientists who have special training in particular
organisms such as mammalogy, ornithology, herpetology, or entomology,
but use those organisms as systems to answer general questions about
Evolutionary biology is partly based on paleontology, which uses the
fossil record to answer questions about the mode and tempo of
evolution, and partly on the developments in areas such as
population genetics and evolutionary theory. Following the
development of DNA fingerprinting techniques in the late 20th century,
the application of these techniques in zoology has increased the
understanding of animal populations. In the 1980s, developmental
biology re-entered evolutionary biology from its initial exclusion
from the modern synthesis through the study of evolutionary
developmental biology. Related fields often considered part of
evolutionary biology are phylogenetics, systematics, and taxonomy.
Scientific classification in zoology, is a method by which zoologists
group and categorize organisms by biological type, such as genus or
Biological classification is a form of scientific taxonomy.
Modern biological classification has its root in the work of Carl
Linnaeus, who grouped species according to shared physical
characteristics. These groupings have since been revised to improve
consistency with the Darwinian principle of common descent. Molecular
phylogenetics, which uses
DNA sequences as data, has driven many
recent revisions and is likely to continue to do so. Biological
classification belongs to the science of zoological systematics.
Linnaeus's table of the animal kingdom from the first edition of
Systema Naturae (1735).
Many scientists now consider the five-kingdom system outdated. Modern
alternative classification systems generally start with the
Archaea (originally Archaebacteria); Bacteria
(originally Eubacteria); Eukaryota (including protists, fungi, plants,
and animals) These domains reflect whether the cells have nuclei
or not, as well as differences in the chemical composition of the cell
Further, each kingdom is broken down recursively until each species is
separately classified. The order is: Domain; kingdom; phylum; class;
order; family; genus; species. The scientific name of an organism is
generated from its genus and species. For example, humans are listed
as Homo sapiens. Homo is the genus, and sapiens the specific epithet,
both of them combined make up the species name. When writing the
scientific name of an organism, it is proper to capitalize the first
letter in the genus and put all of the specific epithet in lowercase.
Additionally, the entire term may be italicized or underlined.
The dominant classification system is called the Linnaean taxonomy. It
includes ranks and binomial nomenclature. The classification,
taxonomy, and nomenclature of zoological organisms is administered by
the International Code of Zoological Nomenclature. A merging draft,
BioCode, was published in 1997 in an attempt to standardize
nomenclature, but has yet to be formally adopted.
Kelp gull chicks peck at red spot on mother's beak to stimulate the
Ethology is the scientific and objective study of animal behavior
under natural conditions, as opposed to behaviourism, which
focuses on behavioral response studies in a laboratory setting.
Ethologists have been particularly concerned with the evolution of
behavior and the understanding of behavior in terms of the theory of
natural selection. In one sense, the first modern ethologist was
Charles Darwin, whose book, The Expression of the Emotions in Man and
Animals, influenced many future ethologists.
Biogeography studies the spatial distribution of organisms on the
Earth, focusing on topics like plate tectonics, climate change,
dispersal and migration, and cladistics. The creation of this study is
widely accredited to Alfred Russel Wallace, a British biologist who
had some of his work jointly published with Charles Darwin.
Branches of zoology
Although the study of animal life is ancient, its scientific
incarnation is relatively modern. This mirrors the transition from
natural history to biology at the start of the 19th century. Since
Hunter and Cuvier, comparative anatomical study has been associated
with morphography, shaping the modern areas of zoological
investigation: anatomy, physiology, histology, embryology, teratology
and ethology. Modern zoology first arose in German and British
universities. In Britain,
Thomas Henry Huxley
Thomas Henry Huxley was a prominent figure.
His ideas were centered on the morphology of animals. Many consider
him the greatest comparative anatomist of the latter half of the 19th
century. Similar to Hunter, his courses were composed of lectures and
laboratory practical classes in contrast to the previous format of
Gradually zoology expanded beyond Huxley's comparative anatomy to
include the following sub-disciplines:
Zoography, also known as descriptive zoology, is the applied science
of describing animals and their habitats
Comparative anatomy studies the structure of animals
Ethology studies animal behavior
The various taxonomically oriented disciplines such as mammalogy,
herpetology, ornithology, and entomology identify and classify species
and study the structures and mechanisms specific to those groups.
Evolutionary biology: Development of both animals and plants is
considered in the articles on evolution, population genetics,
heredity, variation, Mendelism, and reproduction.
Molecular biology studies the common genetic and developmental
mechanisms of animals and plants
Systematics, cladistics, phylogenetics, phylogeography, biogeography,
and taxonomy classify and group species via common descent and
Animal science, the biology of domesticated animals
List of zoologists
Outline of zoology
Timeline of zoology
^ "zoology". Online Etymology Dictionary.
^ Bayrakdar, Mehmet (1986). "Al-Jahiz and the rise of biological
evolution" (PDF). Ankara Üniversitesi İlahiyat Fakültesi Dergisi.
Ankara Üniversitesi İlahiyat Fakültesi. 27 (1): 307–15.
doi:10.1501/Ilhfak_0000000674. Retrieved 21 December 2012.
^ Paul S. Agutter & Denys N. Wheatley (2008). Thinking about Life:
The History and Philosophy of
Biology and Other Sciences. Springer.
p. 43. ISBN 1-4020-8865-5.
Albertus Magnus (1999). On Animals: A Medieval Summa
Zoologica. Johns Hopkins University Press.
^ Lois N. Magner (2002). A History of the Life Sciences, Revised and
Expanded. CRC Press. pp. 133–144.
^ Jan Sapp (2003). "Chapter 7". Genesis: The
Evolution of Biology.
Oxford University Press. ISBN 0-19-515619-6.
^ William Coleman (1978). "Chapter 2".
Biology in the Nineteenth
Century. Cambridge University Press. ISBN 0-521-29293-X.
^ Jerry A. Coyne (2009). Why
Evolution is True. Oxford: Oxford
University Press. p. 17. ISBN 0-19-923084-6.
^ "Appendix: Frequently Asked Questions". Science and Creationism: a
view from the National Academy of Sciences (php) (Second ed.).
Washington, DC: The National Academy of Sciences. 1999. p. 28.
ISBN -0-309-06406-6. Retrieved September 24, 2009.
^ Henry Gray (1918).
Anatomy of the
Human Body. Lea &
^ Jablonski D (1999). "The future of the fossil record". Science. 284
(5423): 2114–16. doi:10.1126/science.284.5423.2114.
^ John H. Gillespie (1998).
Population Genetics: A Concise Guide.
Johns Hopkins Press. ISBN 0-8018-8008-4.
^ Chambers, Geoffrey K.; Curtis, Caitlin; Millar, Craig D.; Huynen,
Leon; Lambert, David M. (2014-01-01). "DNA fingerprinting in zoology:
past, present, future". Investigative Genetics. 5: 3.
doi:10.1186/2041-2223-5-3. ISSN 2041-2223. PMC 3909909 .
^ Vassiliki Betty Smocovitis (1996). Unifying Biology: The
Evolutionary Synthesis and Evolutionary Biology. Princeton University
Press. ISBN 0-691-03343-9.
^ a b Woese C, Kandler O, Wheelis M (1990). "Towards a natural system
of organisms: proposal for the domains Archaea, Bacteria, and
Eucarya". Proc Natl Acad Sci USA. 87 (12): 4576–9.
PMC 54159 . PMID 2112744.
^ Heather Silyn-Roberts (2000). Writing for Science and Engineering:
Papers, Presentation. Oxford: Butterworth-Heinemann. p. 198.
^ John McNeill (4 November 1996). "The BioCode: Integrated biological
nomenclature for the 21st century?". Proceedings of a Mini-Symposium
on Biological Nomenclature in the 21st Century.
^ "Definition of ETHOLOGY". Merriam-Webster. Retrieved 30 October
2012. 2 : the scientific and objective study of animal behaviour
especially under natural conditions
^ Black, J (Jun 2002). "Darwin in the world of emotions" (Free full
text). Journal of the Royal Society of Medicine. 95 (6): 311–3.
doi:10.1258/jrsm.95.6.311. ISSN 0141-0768. PMC 1279921 .
^ Wiley, R. H. (1981). "Social structure and individual ontogenies:
problems of description, mechanism, and evolution" (PDF). Perspectives
in ethology. 4: 105–133. Retrieved 21 December 2012.
^ "zoology". Encyclopedia Britannica. Retrieved 2017-09-13.
At Wikiversity, you can learn
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Online Dictionary of Invertebrate Zoology
Ctenophora (comb jellies)
Cnidaria (jellyfish and relatives)
craniates / vertebrates
Echinodermata (starfish and relatives)
Kinorhyncha (mud dragons)
Priapulida (penis worms)
Nematomorpha (horsehair worms)
Onychophora (velvet worms)
Chaetognatha (arrow worms)
Gnathostomulida (jaw worms)
Dicyemida or Rhombozoa
Annelida (ringed worms)
Nemertea (ribbon worms)
Entoprocta or Kamptozoa
Ectoprocta (moss animals)
Brachiopoda (lamp shells)
Phoronida (horseshoe worms)
Anthozoa inc. corals
Medusozoa inc. jellyfish
Asterozoa inc. starfish
Phyla with ≥5000 extant species bolded
Monoblastozoa (nomen dubium)
Evolutionary developmental biology
Hierarchy of life
Ecosystem > Community (Biocoenosis)
Organism > Organ system
> Organ > Tissue > Cell > Organelle
Biomolecular complex >
Biomolecule) > Atom
Earliest known life forms
Plant morphology terms
Karl Ernst von Baer
Richard C. Banks
Jakob von Uexküll
Alfred Russel Wallace
Timeline of zoology
Zoos, aquariums and aviaries
Types of zoos
Animal theme park
Marine mammal park
Ex situ conservation
In situ conservation
Animals in captivity