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Secretarybird

Secretarybird is a biology topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Secretarybird rather than just read about it. In short: The secretarybird or secretary bird (Sagittarius serpentarius) is a large bird of prey that is endemic to Africa. It is mostly terrestrial, spending most of its time on the ground, and is usually found in the open grasslands and savanna of the sub-Saharan region.

Secretarybird — main illustration
Secretarybird — illustration

Key takeaways

  • Secretarybird belongs to biology; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Secretarybird to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Secretarybird from memory before moving on to harder problems.

Reference excerpt

The secretarybird or secretary bird (Sagittarius serpentarius) is a large bird of prey that is endemic to Africa. It is mostly terrestrial, spending most of its time on the ground, and is usually found in the open grasslands and savanna of the sub-Saharan region. John Frederick Miller described the species in 1779. A member of the order Accipitriformes, which also includes many other diurnal birds of prey such as eagles, hawks, kites, vultures, and harriers, it is placed in its own family, the Sagittariidae. The secretarybird is instantly recognizable as a very large bird with an eagle-like body on crane-like legs that give the bird a height of as much as 1.3 m (4 ft 3 in). The sexes are similar in appearance. Adults have a featherless, red-orange face and predominantly grey plumage, with a flattened dark crest and black flight feathers and thighs. Breeding can take place at any time of year, but tends to be late in the dry season. The nest is built at the top of a thorny tree, and a clutch of one to three eggs is laid. In years with plentiful food, all three young can survive to fledging. The secretarybird hunts and catches prey on the ground, often stomping on victims to kill them. Insects and small vertebrates make up its diet. Although the secretarybird resides over a large range, the results of localized surveys suggest that the total population is experiencing a rapid decline, probably as a result of habitat destruction. The species is therefore classed as endangered by the International Union for Conservation of Nature. The secretarybird appears on the coats of arms of South Africa and Sudan.

Taxonomy

Dutch naturalist Arnout Vosmaer described the secretarybird in 1769 on the basis of a live specimen that had been sent to Holland from the Cape of Good Hope two years earlier by an official of the Dutch East India Company. Vosmaer suggested that the species was called "sagittarius" by the Dutch settlers because its gait was thought to resemble an archer's. He also mentioned that it was known as the "secretarius" by farmers who had domesticated the bird to combat pests around their homesteads, and proposed that the word "secretarius" might be a corruption of "sagittarius". Ian Glenn of the University of the Free State suggests that Vosmaer's "sagittarius" is a misheard or mistranscribed form of "secretarius", rather than the other way around. In 1779 the English illustrator John Frederick Miller included a coloured plate of the secretarybird in his Icones animalium et plantarum and coined the binomial name Falco serpentarius. As the oldest published specific name, serpentarius has priority over later scientific names. The species was assigned to its own genus Sagittarius in 1783 by the French naturalist Johann Hermann in his Tabula affinitatum animalium. The generic name Sagittarius is Latin for "archer", and the specific epithet serpentarius is from Latin serpens meaning "serpent" or "snake". A second edition of Miller's plates was published in 1796 as Cimelia physica, with added text by English naturalist George Shaw, who named it Vultur serpentarius. The French naturalist Georges Cuvier erected the genus Serpentarius in 1798, and the German naturalist Johann Karl Wilhelm Illiger erected the (now synonymous) genus Gypogeranus from the Ancient Greek words gyps "vulture" and geranos "crane" in 1811. In 1835, Irish naturalist William Ogilby spoke at a meeting of the Zoological Society of London and proposed three species of secretarybird, distinguishing those from Senegambia as having broader crest feathers than those from South Africa, and reporting a distinct species from the Philippines based on the writings of Pierre Sonnerat in his Voyage à la Nouvelle-Guinée. There is no other evidence this taxon existed. Despite its large range, the secretarybird is considered monotypic: no subspecies are recognised. The evolutionary relationship of the secretarybird to other raptors had long puzzled ornithologists. The species was usually placed in its own family, the Sagittariidae, within the order Falconiformes. A large molecular phylogenetic study published in 2008 concluded that the secretarybird was sister to a clade containing the ospreys in the family Pandionidae and the kites, hawks, and eagles in the family Accipitridae. The same study found that the falcons in the order Falconiformes were only distantly related to the other diurnal birds of prey. The families Cathartidae, Sagittariidae, Pandionidae, and Accipitridae were therefore moved from the Falconiformes to the resurrected Accipitriformes. A later molecular phylogenetic study published in 2015 confirmed these relationships. The earliest fossils associated with the family are two species from the genus Pelargopappus. The species, from the Oligocene and Miocene, respectively, were discovered in France. The feet in these fossils are more like those of the Accipitridae; these characteristics are suggested to be primitive features within the family. In spite of their age, the two species are not thought to be ancestral to the secretarybird. Though strongly convergent with the modern secretarybird, the extinct raptor Apatosagittarius is thought to be an accipitrid. The International Ornithologists' Union has designated "secretarybird" the official common name for the species. In 1780, French polymath Georges-Louis Leclerc, Comte de Buffon suggested that the name secretary/secrétaire had been chosen because of the long, quill-like feathers at the top of the bird's neck, reminiscent of a quill pen behind the ear of an ancient scribe. In 1977, C. Hilary Fry of Aberdeen University suggested that "secretary" is from the French secrétaire, a corruption of the Arabic صقر الطير saqr et-tair meaning either "hawk of the semidesert" or "hawk that flies". Glenn has dismissed this etymology on the grounds that no evidence supports that the name came through French, instead supporting Buffon's etymology, namely, that the word comes from the Dutch secretaris "secretary", used by settlers in South Africa.

… excerpt ends here. Continue reading the full article.

Illustrations

Secretarybird illustration
Secretarybird illustration
Secretarybird illustration
Secretarybird: Plate from John Frederick Miller's Icones animalium et plantarum, published 1779, with the original binomial name
Plate from John Frederick Miller's Icones animalium et plantarum, published 1779, with the original binomial name
Secretarybird: A pair atop a tree
A pair atop a tree

Worked examples

Example 1 — a first encounter with Secretarybird

Start with the simplest possible case. Write down what Secretarybird claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Secretarybird before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Secretarybird ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Secretarybird

In research
Secretarybird appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Secretarybird in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Secretarybird is common in secondary-school and first-year university syllabi. It links to neighbouring topics Accipitriformes, Apex predators, Birds described in 1779, so understanding it makes those chapters shorter.
In everyday life
Look for Secretarybird outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Secretarybird in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Secretarybird means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Secretarybird out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Secretarybird in simple terms?

The secretarybird or secretary bird (Sagittarius serpentarius) is a large bird of prey that is endemic to Africa. It is mostly terrestrial, spending most of its time on the ground, and is usually found in the open grasslands and savanna of the sub-Saharan region.

Why does Secretarybird matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Secretarybird?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Secretarybird.

Tags

  • Accipitriformes
  • Apex predators
  • Birds described in 1779
  • Birds of Sub-Saharan Africa
  • Birds of prey
  • Birds of prey of Africa
  • Falconiformes (sensu lato)
  • IUCN Red List endangered species
  • National symbols of South Africa
  • National symbols of Sudan
  • Taxa named by John Frederick Miller

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