History of Ecology
The term ecology was first used by German zoologist Ernst Haeckel (1869), however, this science has its origins in other sciences such as biology, geology and evolution among others.
Lamarck with his theory of evolution, proposed that the environment is in constant transformation, by which agencies need change and make an effort to achieve this, and this is a mechanism of evolution, one of the main bases of ecology taking into account the relationships of organisms and their environment.
On the other hand, not only the agencies change and evolve, but also the Earth’s crust. The English geologist Charles Lyell found that the Earth’s crust is the result of gradual changes throughout the history of the planet. Giving way to the transformation of ecosystems and their functions.
Modern ecology, actually had its principles with the development of the theory of Darwinian evolution. He noted that the environment is constantly changing which causes the agencies with best adaptations are those who survive by the mechanism of natural selection. Highlighting the importance of the interaction of organisms with their environment.
Although the ecology was born in the 19th century, with the work of Haeckel, ecology began to flourish until the 20th century, when the first ecological journals and ecological societies appeared.
The definition of Haeckel, has been the subject of interpretations something different and perhaps more profound since 1900. For example, the English ecologist Charles Elton defined ecology as the “scientific natural history” which deals with the “sociology and economy of animals”. An American plant ecologist, Frederick Clements, considered that ecology was “the science of the community”, and the contemporary American ecologist Eugene Odum defined, perhaps too widely, as ‘the study of the structure and function of nature’.
The first conceptions of the “genotypic” begin in the third decade of the 20th century or ecology of communities, where the concept of community as superior hierarchical level of organization, includes different people interacting with its environment. However this concept, attached to the biological origin of ecology, once again was decoupled agencies that defined it. Later, as it is the case still, stood “biotope” as a place where is found the community but by characteristics inherent in the physical environment, not by their relationship to agencies.
In the Decade of the 40s, Tansley (1935) proposed the concept of “ecosystem”. This term was later developed by Lindeman (1941), who conceived it from exchanges of energy, in response to the need for concepts that link various agencies to their physical environments. In the texts of ecology of the 1950s and still later, designating ecosystem as the sum of the various communities (or biocoenosis) and biotope (inert atmosphere). In this type of definition is notable as agencies or the community are made disociadamente of the environment, because that ecosystem is defined by the sum of terms.
http://environment-ecology.com/history-of-ecology/594-history-of-ecology.html
The term ecology was first used by German zoologist Ernst Haeckel (1869), however, this science has its origins in other sciences such as biology, geology and evolution among others.
Lamarck with his theory of evolution, proposed that the environment is in constant transformation, by which agencies need change and make an effort to achieve this, and this is a mechanism of evolution, one of the main bases of ecology taking into account the relationships of organisms and their environment.
On the other hand, not only the agencies change and evolve, but also the Earth’s crust. The English geologist Charles Lyell found that the Earth’s crust is the result of gradual changes throughout the history of the planet. Giving way to the transformation of ecosystems and their functions.
Modern ecology, actually had its principles with the development of the theory of Darwinian evolution. He noted that the environment is constantly changing which causes the agencies with best adaptations are those who survive by the mechanism of natural selection. Highlighting the importance of the interaction of organisms with their environment.
Although the ecology was born in the 19th century, with the work of Haeckel, ecology began to flourish until the 20th century, when the first ecological journals and ecological societies appeared.
The definition of Haeckel, has been the subject of interpretations something different and perhaps more profound since 1900. For example, the English ecologist Charles Elton defined ecology as the “scientific natural history” which deals with the “sociology and economy of animals”. An American plant ecologist, Frederick Clements, considered that ecology was “the science of the community”, and the contemporary American ecologist Eugene Odum defined, perhaps too widely, as ‘the study of the structure and function of nature’.
The first conceptions of the “genotypic” begin in the third decade of the 20th century or ecology of communities, where the concept of community as superior hierarchical level of organization, includes different people interacting with its environment. However this concept, attached to the biological origin of ecology, once again was decoupled agencies that defined it. Later, as it is the case still, stood “biotope” as a place where is found the community but by characteristics inherent in the physical environment, not by their relationship to agencies.
In the Decade of the 40s, Tansley (1935) proposed the concept of “ecosystem”. This term was later developed by Lindeman (1941), who conceived it from exchanges of energy, in response to the need for concepts that link various agencies to their physical environments. In the texts of ecology of the 1950s and still later, designating ecosystem as the sum of the various communities (or biocoenosis) and biotope (inert atmosphere). In this type of definition is notable as agencies or the community are made disociadamente of the environment, because that ecosystem is defined by the sum of terms.
http://environment-ecology.com/history-of-ecology/594-history-of-ecology.html
Animal ecology is one area of zoology .Zoology studies consist of areas such as animal species and their taxonomic relations (systematics), animal distribution and abundance within their range (zoogeography), interaction between species, individuals and their environment (ecology) and whole animals as functional units (physiology). An ecologist most often operates with data gathered in the field; the data being either descriptive, inventory, comparative or experimental. Physiologists conduct experimental studies on the structure and function of animal tissues and organs, usually working in the laboratory. The different branches of zoology often overlap each other, and researchers must deal with a wide range of questions, for example, in the fields of ecophysiology, or ecological biogeography.
Species distribution is the manner in which a biological taxon is spatially arranged. Species distribution is not to be confused with dispersal, which is the movement of individuals away from their area of origin or from centers of high population density. A similar concept is the species range. A species range is often represented with a species range map. Biogeographers try to understand the factors determining a species' distribution. The pattern of distribution is not permanent for each species. Distribution patterns can change seasonally, in response to the availability of resources, and also depending on the scale at which they are viewed. Dispersion usually takes place at the time of reproduction. Populations within a species are translocated through many methods, including dispersal by people, wind, water and animals. People are one of the largest distributors due to the current trends in globalization and the expanse of the transportation industry. For example, large tankers often fill their ballasts with water at one port and empty them in another, causing a wider distribution of aquatic species.
The Annelida are a medium sized phylum of more than 9,000 species of worms. Most species prefer aquatic environments, but there are also a number of well know terrestrial species. Only a few species of annelids are commonly known to human beings, these include the delightful Rain, Dew or Earthworms that work so hard to make our soils healthy, the Ragworms and Lugworms used by marine fishermen and the much smaller Tubifex or Red worms used by aquarists to feed their fish. In many countries people are still familiar with Medicinal leeches, and people who live closer to nature are naturally more familiar with a much wider range of Annelids than those who live in cities. Despite The earthworms, of which there are many species, are exceedingly important in soil creation, particularly in temperate areas. Without them, agriculture and perhaps the whole of human society as we know it would never have evolved. Like so much of the unnoticed invertebrate world earthworms are essential to our very existence. In marine environments the numerous species of Polychaetes play a fundamentally important role in the maintenance of food chains and the whole ecological balance of the seas, thus supporting the seemingly endless stocks of fish we like to eat.
One of the strangest ways that humans relate to Annelids is in the hobby of 'Worm Charming'. This involves enticing earthworms from their holes (catching them), originally it was a means of acquiring worms for bait, but now-a-days it is a sport. The world record as far as I know is held by Tom Shufflebotham who charmed 511 worms from their underground hideouts from an area of 3 square metres in only 30 minutes during the 1980 Annual Worm Charming Championships held in Cheshire UK. The rules specify that the worms must be brought to the surface without using refreshment, stimulation, drugs or digging. Tom used a method called twanging which involves sticking a 4-pronged pitchfork into the ground and twanging it. Annelids range in size from the Giant Earthworms, of which Michrochaetus rappi (Michrochaetus michrochaetus) is the largest, this magnificent animal has an average length of 1.36 m (54 ins) and a record breaking specimen has been recorded that measured 6.7 metres (22 ft) in length, it was 2cm (0.8 ins) in diametre. Larger worms have been reported but not scientifically proven. The smallest Annelid known to science is Chaetogaster annandalai which is full grown at 0.5 mm (0.02 ins). Annelids have two main modes of existence, they either live rather quietly in holes or they live more active lives. The basic Annelid body plan is one of a head followed by a long thin body of numerous similar segments ending in a small tail. The head consists of a mouth (prostomium) and sometimes a peristomium, and the tail is more correctly called a pygidium, as it is not really a tail. Annelids are coelomate animals meaning they have a true coelom within their body. They have sets chaetae attached to each body segment, and these can be simple and small as in the Earthworms or complex and varied as in many Polychaetes. The head is often reduced and difficult to distinguish in the hole living species, but may be easily recognised, with eyes and other sensory devices in those species living a more active life. Annelids are coelomate animals (meaning they have a true coelom, even if this is reduced secondarily). They normally have long thin bodies composed of a series of identical segments. These segments lie between the head, comprised of a prostomium, a mouth and sometimes a peristomium, and a tail called a pygidium. Growth occurs both laterally, by enlargement of the segments during the juvenile stages, and through the addition of new segments. New segments are produced by the foremost section of the pygidium. In some species they are produced throughout the animals life but in many species production stops once a certain set number of segments has been achieved. The Invertebrates, by Barnes, Calow and Olive |
The mollusks constitute one of the largest phyla of animals, both in numbers of living species (at least 47,000, and perhaps many more) and in numbers of individuals.
Asignificant characteristic of mollusks is their possession of a coelom, a fluid-filled cavity that develops within the mesoderm. The coelom not only functions as a hydrostatic skeleton but also provides space within which the internal organs can be suspended by the mesenteries. All mollusks have a soft body (their name is derived from the Latin word mollus, meaning "soft"), which is generally protected by a hard, calcium- containing shell. In some forms however, the shell has been lost in the course of evolution, as in slugs and octopuses, or greatly reduced in size and internalized, as in squids. Structurally, mollusks are quite distinct from all other animals. However, all modern mollusks have the same fundamental body plan. There are three distinct body zones: a head-foot, which contains both the sensory and motor organs; a visceral mass, which contains the well-developed organs of digestion, excretion, and reproduction; and a mantle, a specialized tissue formed from folds of the dorsal body wall, that hangs over and enfolds the visceral mass and that secretes the shell. The mantle cavity, a space between the mantle and the visceral mass, houses the gills; the digestive, excretory, and reproductive systems discharge into it. Mollusks are also characterized by a toothed tongue, the radula, composed primarily of chitin. The radula serves both to scrape off algae and other food materials and also to convey them backward to the digestive tract. In some species, it is also used in combat. http://animaldiversity.ummz.umich.edu/mollusca/bivalvia.html Phylum Arthropoda (arthro = joint; poda = foot) is the most numerous phylum of all living organisms, both in number of species and in number of individuals. One, very conservative, estimate is that there are well over one million species of insects alone. In terms of number of individuals, there are more ants than anything else, and in terms of numbers of species, there are more kinds of beetles than anything else: 40 to 50% of all insect species are beetles. There are more species of insects than all other plants and animals together.
An arthropod has a segmented body covered by an exoskeleton made from chitin and other chemicals. This exoskeleton serves as protection and provides places for muscle attachment. Arthropods must molt because their exoskeletons don’t grow with them. Arthropods have open circulatory systems consisting of a dorsal heart which collects blood from the body cavity and pumps it back into the body cavity again. In insects, the anterior portion of the heart (which is located in the abdomen) is extended into a tube that is called an aorta which directs the blood forward as it goes out into the body cavity. Arthropods have a well-developed, mesodermal, ventral, solid nerve cord and well-developed sense organs. The body feature from which the phylum takes its name is the jointed appendages, which include antennae and mouthparts as well as walking legs. It is thought that the early arthropod ancestors (descended from organisms that looked like marine worms or, later, Peripatus) looked sort of like a centipede: they had a number of body segments, each with a pair of jointed appendages. From there, some of these segments became fused to form a head and some of the appendages became modified to form mouthparts or antennae. Early on, there was an evolutionary split which led to the various modern subphyla and classes. Currently, three living subphyla are recognized, with trilobites representing an extinct fourth subphylum. Arthropods1997 by J. Stein Carter The Echinodermata
(from the Greek meaning spiny skin), is a phylum containing some 13,000 extinct and 7,000 extant species. Living representatives are only found in marine environment, making the phylum the largest lacking terrestrial and fresh water forms. Echinoderms evolved from bilaterally symmetric animals exhibiting fivefold radial symmetry in portions of their body at some stage of life. This pentameral symmetry is readily apparent in familiar adult starfish and sand dollars. Other echinoderms both extant and extinct lack the five point morphology because it was lost somewhere during development (i.e., during ontogeny).Echinoderms have a vascular system that carries water and which in some echinoderms end in suckered feet enabling the creature to grip and move objects. Reproduction in Echinoderms reproduction is usually via external fertilization through eggs and sperm discharged into the water, and the majority of echinoderms have several planktonic larval stages before reverting to a sessile existence on the seafloor. Since most echinoderms have some type of calcareous support exoskeleton (actually often interlocking plates of calcium carbonate), there exists an extensive fossil record tracing echinoderm evolution. Yet, many aspects of their early evolutionary origins are confounded, such that the classification table below is but one of many interpretations to be found in the literature. Importantly, the Echinodermata phylogenetic relationship to other phyla is poorly understood because they were already well differentiated by the Cambrian, and their unique characteristics are not present in other groups. While echinoderms are known from the Cambrian on, the Vendian period has a few soft-bodied fossils that are putative echinoderms or their ancestors. These include Arkarua and Tribrachidium from the Ediacara Hills of Australia. Homalozoans, from which echinoderm may have descended, and eocrinoids, that are not directly ancestral to the true crinoids, are abundant in the early Cambrian fossil record. http://www.fossilmuseum.net |
Chordates are defined as organisms that possess a structure called a notochord, at least during some part of their development. The notochord is a rod that extends most of the length of the body when it is fully developed. Lying dorsal to the gut but ventral to the central nervous system, it stiffens the body and acts as support during locomotion. Other characteristics shared by chordates include the following (from Hickman and Roberts, 1994):
For More Information Find Chordata information at D. Class Reptalia: ReptilesThe Class Reptilia, or reptiles, traditionally included a diverse group of animals: turtles, snakes, lizards and crocodiles, alligators and caimans. Many scientists believe that birds also belong in this class.Characteristics of Reptiles:Animals in the Class Reptilia:
http://marinelife.about.com E. Class Aves: Birds
Characteristics of Class Aves
1. Body usually spindle shaped, with four divisions: head, neck, trunk, and tail; neck disproportionately long for balancing and food gathering. 2. Limbs paired; forelimbs usually modified for flying; posterior pair variously adapted for perching, walking, and swimming; foot with four toes (two or three toes in some) 3. Epidermal covering of feathers and leg scales; thin integument of epidermis and dermis; no sweat glands; oil or preen gland at base of tail; pinna of ear rudimentary 4. Fully ossified skeleton with air cavities; skull bones fused with one occipital condyle; each jaw covered with a keratinized sheath, forming a beak; no teeth; ribs with strengthening, uncinate processes; posterior caudal vertebrae reduced and fused as the pygostyle; pelvic girdle a synsacrum; aerythrocytes sternum usually well developed with keel; single bone in middle ear 5. Nervous system well developed, with 12 pairs of cranial nerves and brain with large cerebellum and optic lobes 6. Circulatory system consists of four-chambered heart with two atria and two ventricles; completely separate pulmonary and systematic circuits; right aortic arch persisting; nucleated erythrocytes 7. Endodermic 8. Respiration by slightly expansible lungs, with thin air sacs among the visceral organs and skeleton; syrinx (voice box) near junction of trachea and bronchi 9. Excretory system includes metanephric kidneys; ureters open into cloaca; no bladder; semisolid urine; uric acid main nitrogenous waste 10. Sexes separate; testes paired, with the vas deferens opening into the cloaca; females have left ovary and oviduct only; copulatory organ (penis) only in ducks, geese, paleognathids and a few athers 11. Fertilization internal; amniotic eggs with much yolk and hard, calcareous shells; embryonic membranes in egg during development; incubation external; young active at hatching (precocial) or helpless and naked (altricial); sex determined by females (females heterogametic) |
Click to set custom HTML
A. Class Chondrichthyes:
|