science

Thayer Expedition

Thayer Expedition is a science 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 Thayer Expedition rather than just read about it. In short: The Thayer Expedition was an American scientific expedition to Brazil, sponsored by Boston businessman Nathaniel Thayer Jr. It was a biological and geological expedition undertaken by multiple scientists, several based at Harvard University, between April 1865 and August 1866.

Key takeaways

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

Reference excerpt

The Thayer Expedition was an American scientific expedition to Brazil, sponsored by Boston businessman Nathaniel Thayer Jr. It was a biological and geological expedition undertaken by multiple scientists, several based at Harvard University, between April 1865 and August 1866. Scientists collected tens of thousands of specimens, some later recognized as new species. Most of the specimens collected during the expedition ended up in the collections of Harvard's Museum of Comparative Zoology, founded by Louis Agassiz, the leader of the expedition. The Thayer Expedition took place at the end of the American Civil War, with the ocean voyage from New York City to Rio de Janeiro beginning on April 2, just a week prior to Lee's surrender at Appomattox. The expedition sailed on board the S.S. Colorado, owned by the Pacific Mail Steamship Company, and docked in Rio de Janeiro on April 23. They explored Brazil from the coast to the Tocantins River and along its tributaries to the borders of Colombia and Peru.

Participants The expedition included the following named participants:

Louis Agassiz, Swiss-American zoologist, ichthyologist, geologist, and leader of the expedition. His primary goal for the expedition was the collection of Brazilian freshwater fish specimens. Elizabeth Cabot Agassiz, American naturalist, the expedition's main writer and record-keeper, wife of Agassiz. Joel Asaph Allen, American curator of ornithology at the Museum of Comparative Zoology. John Gould Anthony, American curator of conchology at the Museum of Comparative Zoology. Jacques Burkhardt, Swiss scientific illustrator who painted or drew hundreds of fish specimens during the expedition. Charles Frederick Hartt, Canadian-American geologist, paleontologist and naturalist who studied Brazilian geology. Orestes St. John, American geologist and paleontologist who had been trained by Agassiz. George Sceva, American preparator, mainly of fossils, for the Museum of Comparative Zoology and others. Six American volunteers: William James (famous future philosopher and psychologist), Herbert Edson Copeland, Newton Dexter, Walter Hunnewell, Stephen Van Rensselaer Thayer (son of expedition sponsor Nathaniel Thayer), and Thomas Ward. João Martins da Silva Coutinho, Brazilian army major and attache of the Expedition. D. Bourget, French naturalist residing in Rio de Janeiro.

Species collected (partial list)

Hyphessobrycon bentosi Astyanax brevirhinus Leporinus agassizii Gymnocoryumbus thayeri Thayeria obliquua Astyanax asymmetricus Astyanax symmetricus Astyanax zonatus Astyanax anterior Astyanax bourgeti Astyanax bimaculatus borealis Astyanax janeiroensis Astyanax goyacensis Astyanax brevirhimus Astyanax giton Astyanax albeolus Astyanax fasciatus parahybae Astyanax scabripinnis intermedius Astyanax multidens Astyanax gracilior Deuterodon pedri Deuterodon parahybae Pristella Psellogrammus Hemigrammus coeruleus Durbin Hemigrammus levis Durbin Hyphessobrycon compressus milleri Durbin Hyphessobrycon serpae Durbin Hyphessobrycon copelandi Durbin Hyphessobrycon panamensis Durbin Hyphessobrycon melazonatus Durbin Moenkhausia latissimus Moenkhausia jamesi Moenkhausia comma Moenkhausia justae Moenkhausia melogrammus Moenkhausia australe Moenkhausia barbouri Moenkhausia dichrourus intermedius Moenkhausia llepidurus latus Moenkhausia llepidurus içae Moenkhausia llepidurus gracilimus Moenkhausia cotinho Moenkhausia ceros Bryconamericus heteresthes Bryconamericus stramineus Bryconamericus boops Bryconamericus breviceps Bryconamericus peruanus ricae Brycochandus durbini Creatochanes gracilis Poptella

References

External links Archives at Ernst Mayr Library of the Museum of Comparative Zoology

Illustrations

Worked examples

Example 1 — a first encounter with Thayer Expedition

Start with the simplest possible case. Write down what Thayer Expedition claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, 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 Thayer Expedition 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 Thayer Expedition 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 Thayer Expedition

In research: Thayer Expedition appears in science 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 Thayer Expedition 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: Thayer Expedition is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1860s in South America, 1865 in science, 1866 in science, so understanding it makes those chapters shorter.
In everyday life: Look for Thayer Expedition 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 Thayer Expedition in 20 minutes

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

Frequently asked questions

What is Thayer Expedition in simple terms?

Why does Thayer Expedition matter?

Because it connects several science 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 Thayer Expedition?

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 Thayer Expedition.