Phycology (from Greek φῦκος, phykos, "seaweed"; and -λογία, -logia) is the scientific study of algae. Also known as algology, phycology is a branch of life science and often is regarded as a subdiscipline of botany.
Algae are important as primary producers in aquatic ecosystems. Most algae are eukaryotic, photosynthetic organisms that live in a wet environment. They are distinguished from the higher plants by a lack of true roots, stems or leaves. They do not flower. Many species are single-celled and microscopic (including phytoplankton and other microalgae); many others are multicellular to one degree or another, some of these growing to large size (for example, seaweeds such as kelp and Sargassum).
Phycologists typically focus on either freshwater or ocean algae, and further within those areas, either diatoms or soft algae.
While both the ancient Greeks and Romans knew of algae, and the ancient Chinese even cultivated certain varieties as food, the scientific study of algae began in the late 18th century with the description and naming of Fucus maximus (now Ecklonia maxima) in 1757 by Pehr Osbeck. This was followed by the descriptive work of scholars such as Dawson Turner and Carl Adolph Agardh, but it was not until later in the 19th century that efforts were made by J.V. Lamouroux and William Henry Harvey to create significant groupings within the algae. Harvey has been called "the father of modern phycology" in part for his division of the algae into four major divisions based upon their pigmentation.
It was in the late 19th and early 20th century, that phycology became a recognized field of its own. Men such as Friedrich Traugott Kützing continued the descriptive work. In Japan, beginning in 1889, Kintarô Okamura not only provided detailed descriptions of Japanese coastal algae, he also provided comprehensive analysis of their distribution. Although R. K. Greville published his Algae Britannicae as early as 1830, it was not until 1902 with the publication of A Catalogue of the British Marine Algae by Edward Arthur Lionel Batters that the systematic correlation of records, extensive distribution mapping and the development of identification keys began in earnest. In 1899-1900, Anna Weber-Van Bosse, a Dutch Phycologist travelled on the Siboga expedition and later in 1904, published The Corallinaceae of the Siboga-expedition.
As early as 1803 Jean Pierre Étienne Vaucher had published on the isogamy (sexual conjugation) in the algae, but it was in the early 20th century that reproduction and development began to be extensively studied. The 1935 and 1945 comprehensive volumes of Felix Eugen Fritsch consolidated what was then known about the morphology and reproduction of the algae. This was followed in the 1950s by the development of area checklists, led by Mary W. Parke with her 1931 Manx Algae and followed in 1953 by her "A preliminary check-list of British marine algae" Although Lily Newton's 1931 Handbook provided the first identification key for the algae of the British Isles, it wasn't until the 1960s that the development of such keys became routine. The 1980s with the new emphasis on ecology saw increased study of algal communities, and the place of algae in larger plant communities, and provided an additional tool for explaining geographical variation.
Chroomonadaceae is a family of cryptomonads first recognized by Clay et al in 1999 as including genera Chroomonas, Falcomonas, and Komma. Following a molecular phylogenic study in 2002, Hemiselmis was also placed within the Chroomonadaceae. Today, the family is generally recognized as sister to the Pyrenomonadaceae.
They are one of only two groups of cryptomonads (alongside Rhinomonas) to lack a rhizostyle. They are also distinguished by the lack of a cleavage furrow and the presence of several phycocyanins and phycoerythrins not observed in any other cryptomonad taxa.Coscinodiscophyceae
The Coscinodiscophyceae are a class of diatoms. They are similar to the Centrales, a traditional, paraphyletic subdivision of the heterokont algae known as diatoms. The order is named for the shape of the cell walls (or valves or frustules) of centric diatoms, which are circular or ellipsoid in valve view. The valves often bear radially symmetrical ornamental patterns that can appear as dots when viewed with an optical microscope. Some also bear spines on their valves, which may either increase cell surface area and reduce sinking, or act as a deterrent to zooplankton grazers. Unlike pennate diatoms, centric diatoms never have a raphe.
In terms of cell cycle, vegetative cells are diploid and undergo mitosis during normal cell division. In sexual species, oogamous meiosis produces haploid gametes, either ova or sperm cells. These fuse to produce a zygote which expands in size to develop into an auxospore from which full-sized vegetative cells are produced.
In some taxonomy schemes, the centric diatoms are known instead as order Coscinodiscophyceae, and in some schemes as order Biddulphiales. However, diatom taxonomy is changing due to the development of new molecular and genetical analysis tools.Dictyotales
Dictyotales is a large order in the brown algae (class Phaeophyceae). Members of this order generally prefer warmer waters than other brown algae. One genus in this order is calcareous, Padina, the only calcareous member of this phylum.Dictyota dominates 70% of the benthos biomass in the Florida Keys reef tract. The successful spread of this alga is due in part to its ability to asexually reproduce from fragments created by "biotic and abiotic disturbances".Gavino Trono
Gavino Cajulao Trono Jr., Ph.D. (born November 9, 1931) is a Filipino biologist dubbed as the "Father of Kappaphycus farming". He was conferred the rank of National Scientist of the Philippines for contributions to the study of tropical marine phycology, focusing on seaweed biodiversity. He is currently working as a technical consultant for the Food and Agriculture Organization (FAO) Aquaculture Seaweed Research and Development and is a professor emeritus of the University of the Philippines Marine Science Institute.Gymnodinium
Gymnodinium is a genus of dinoflagellates, a type of marine plankton. It is one of the few naked dinoflagellates, or species lacking armor (cellulosic plates). Since 2000, the species which had been considered to be part of Gymnodinium have been divided into several genera, based on the nature of the apical groove and partial LSU rDNA sequence data. Amphidinium was redefined later. Gymnodinium belong to red dinoflagellates that, in concentration, can cause red tides.
Gymnodinium sensu stricto
TakayamaHistory of phycology
The history of phycology is the history of the scientific study of algae. Human interest in plants as food goes back into the origins of the species and knowledge of algae can be traced back more than two thousand years. However, only in the last three hundred years has that knowledge evolved into a rapidly developing science.Journal of Phycology
The Journal of Phycology is a bimonthly peer-reviewed scientific journal of phycology (the study of algae), published by John Wiley & Sons, Inc. on behalf of the Phycological Society of America. The journal was established in 1965 and published quarterly until 1992, when it changed to a bimonthly format.Klebsormidiaceae
The Klebsormidiaceae are a family containing three genera of charophyte green alga forming multicellular, non-branching filaments. A fourth genus Chlorokybus is sometimes included as well, but this problematic and poorly known genus is sometimes placed in a separate class Chlorokybophyceae.
Klebsormidiacea may be sister to Phragmoplastophyta, together forming the Streptophyte clade.
The genera Koliella and Raphidonema were formerly classified as close relatives of Klebsormidium, based on similarities in cell division. However, analysis of both nuclear and chloroplast DNA shows that both of these genera belong to the class Trebouxiophyceae and are not charophytes. Interfilum (previously in Ulotrichaceae) also emerged within this group.Macrocystis pyrifera
Macrocystis pyrifera, commonly known as giant kelp or giant bladder kelp, is a species of kelp (large brown algae), and one of four species in the genus Macrocystis. Giant kelp is common along the coast of the eastern Pacific Ocean, from Baja California north to southeast Alaska, and is also found in the southern oceans near South America, South Africa, Australia, and New Zealand. Individual algae may grow to more than 45 metres (150 feet) long at a rate of as much as 60 cm (2 ft) per day. Giant kelp grows in dense stands known as kelp forests, which are home to many marine animals that depend on the algae for food or shelter. The primary commercial product obtained from giant kelp is alginate, but humans also harvest this species on a limited basis for use directly as food, as it is rich in iodine, potassium, and other minerals. It can be used in cooking in many of the ways other sea vegetables are used, and particularly serves to add flavor to bean dishes.Mastigoneme
Mastigonemes are lateral "hairs" found covering the flagella of heterokont and cryptophyte algae. They are approximately 15 nm in diameter, and usually consist of a tubular shaft that itself terminates in smaller "hairs". It is believed that they assist in locomotion by increasing the surface area of a flagellum.
Typology of flagella with hairs:
whiplash flagella (= smooth, acronematic flagella): without hairs, e.g., in Opisthokonta
hairy flagella (= tinsel, flimmer, pleuronematic flagella): with hairs (= mastigonemes sensu lato), divided in:
with fine hairs (= non tubular, or simple hairs): occurs in Euglenophyceae, Dinoflagellata, some Haptophyceae (Pavlovales)
with stiff hairs (= tubular hairs, retronemes, mastigonemes sensu stricto), divided in:
bipartite hairs: with two regions. Occurs in Cryptophyceae, Prasinophyceae, and some Heterokonta
tripartite (= straminipilous) hairs: with three regions (a base, a tubular shaft, and one or more terminal hairs). Occurs in most HeterokontaOnslowiaceae
Onslowiaceae is the only family in order Onslowiales in the brown algae (class Phaeophyceae). The family contains only the genera Onslowia and Verosphacela.Phycological Society of America
The Phycological Society of America (PSA) is a professional society, founded in 1946, that is dedicated to the advancement of phycology, the study of algae. The PSA is responsible for the publication of Journal of Phycology and organizes annual conferences among other events that aid in the advancement of related algal sciences.
Membership in the Phycological Society of America is open to anyone from any nation who is concerned with the physiology, taxonomy, molecular biology, experimental biology, cell biology, and developmental biology of related algal sciences. As of 2012, membership was approximately 2,000 from 63 countries.Phycological Society of India
The Phycological Society of India was founded and registered as Society on 1962. Prof. M. O. P. Iyengar was the first President of the society. Prof. Vidyavati, former Vice-Chancellor, Kakatiya University, Telangana, India is the President now.
The Phycological Society of India promotes interest and studies in various branches of phycology.Pit connection
In algal anatomy, a pit connection is a hole in the septum between two algal cells, and is found only in the red algae − specifically, all orders except the Porphyridiales and haploid Bangiales. They are often stoppered with proteinaceous "pit plugs". By contrast, many fungi (only ascomycetes and basidomycetes, as most other groups lack septa) contain septal pores − an unrelated phenomenon.Pneumatocyst
In phycology, a pneumatocyst is a floating structure that contains gas found on brown seaweed. A seaweed's thallus may have more than one. They provide buoyancy to lift the blades toward the surface, allowing them to receive more sunlight for photosynthesis.
The proportion of gases in the pneumatocysts varies depending on the physiological status of the alga and the partial pressure of gases in the surrounding air or water. The pneumatocyst can hold O2, CO2, N2, and CO.Protistology
Protistology is a scientific discipline devoted to the study of protists, a highly diverse group of eukaryotic organisms. Its field of study overlaps with more traditional disciplines of phycology, mycology, and protozoology, just as protists, which, being a paraphyletic group embrace algae, some organisms regarded previously as primitive fungi, and protozoa ("animal" motile protists lacking chloroplasts).Receptacle (botany)
In botany, the receptacle refers to vegetative tissues near the end of reproductive stems that are situated below or encase the reproductive organs.Seaweed collecting
Seaweed collecting is the process of collecting, drying and pressing seaweed. It became popular as a pastime in the Victorian era and remains a hobby today.Wendy Nelson
Wendy Alison Nelson is a New Zealand marine scientist and world expert in phycology. She is New Zealand's leading authority on seaweeds. Nelson is particularly interested in the biosystematics of seaweeds/macroalgae of New Zealand, with research on floristics, evolution and phylogeny, as well as ecology, and life history studies of marine algae. Recently she has worked on the systematics and biology of red algae including coralline algae, distribution and diversity of seaweeds in harbours and soft sediment habitats, and seaweeds of the Ross Sea and Balleny Islands.
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