biology

Naashoibitosaurus

Naashoibitosaurus 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 Naashoibitosaurus rather than just read about it. In short: Naashoibitosaurus (from Navajo naʼashǫ́ʼii bitooh—"creek lizard") is a genus of hadrosaurid dinosaur that lived about 73 million years ago, in the Late Cretaceous, and was found in the Kirtland Formation of the San Juan Basin in New Mexico, United States. Only a partial skeleton has been found to date.

Key takeaways

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

Reference excerpt

Naashoibitosaurus (from Navajo naʼashǫ́ʼii bitooh—"creek lizard") is a genus of hadrosaurid dinosaur that lived about 73 million years ago, in the Late Cretaceous, and was found in the Kirtland Formation of the San Juan Basin in New Mexico, United States. Only a partial skeleton has been found to date. It was first described as a specimen of Kritosaurus by Jack Horner, and has been intertwined with the taxon since its description.

History Befitting a genus with a confusing taxonomic history, the name of this genus is based on an error. David Gillette and David Thomas collected the type and only known specimen from what was thought to be the Naashoibito Member of the Kirtland Formation, the youngest member of the Kirtland; this was commemorated in the name. Instead, it came from the older, late Campanian-age De-na-zin Member. Horner described the skull in 1992 as that of an immature Kritosaurus, using it as evidence that Gryposaurus was different from Kritosaurus. At the same time, Hunt and Lucas were describing the postcrania as belonging to Edmontosaurus saskatchewanensis. When the disconnect became apparent, Hunt and Lucas gave the specimen its own generic name, because the skull did not agree with an edmontosaur, and they considered Kritosaurus indeterminate and thus not usable. Their assessment was challenged in 2000 by Thomas Williamson, who found the morphological differences between it and Kritosaurus to be due to the skulls in question being from individuals of different ages. Unlike Hunt and Lucas, he considered the type skull of Kritosaurus to be diagnostic and thus could compare it to Naashoibitosaurus. He returned to Horner's argument, noting as Horner had that the nasal crest in other hadrosaurines like Prosaurolophus moves back on the skull during growth. He also pointed out that the specimen's provenance was incorrect; instead of being from younger rocks than Kritosaurus, it is from rocks of about the same age. The next major review, in the second edition of The Dinosauria, again separated the two. The absence of the beak and lower jaw in the partial skull of Naashoibitosaurus makes comparison even more difficult. A 2014 study agreed with previous authors that Naashoibitosaurus is similar to Kritosaurus, but found it to be a distinct species.

Description Naashoibitosaurus, based as it is on a single partial skeleton (NMMNH P-16106), is not well known in terms of anatomy. Its skull, the most thoroughly described portion, has a low nasal crest that peaks in front of the eyes, but does not strongly arch as in Gryposaurus.

Classification Naashoibitosaurus is a saurolophine hadrosaurid, a "flat-headed or solid-crested duckbill". It is closest to the solid-crested forms like Saurolophus. If it is the same as Kritosaurus, Kritosaurus would be used because it is the older name, but its position vis-a-vis other duckbills would be the same.

Paleobiology As a hadrosaurid, Naashoibitosaurus would have been a large bipedal/quadrupedal herbivore, eating plants with a sophisticated skull that permitted a grinding motion analogous to chewing. Its teeth were continually replacing and packed into dental batteries that contained hundreds of teeth, only a relative handful of which were in use at any time. Plant material would have been cropped by its broad beak, and held in the jaws by a cheek-like organ. Feeding would have been from the ground up to ~4 meters (13 ft) above. If it was a separate genus, how it would have partitioned resources with the similar Kritosaurus is unknown.

Illustrations

Worked examples

Example 1 — a first encounter with Naashoibitosaurus

Start with the simplest possible case. Write down what Naashoibitosaurus 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 Naashoibitosaurus 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 Naashoibitosaurus 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 Naashoibitosaurus

In research: Naashoibitosaurus 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 Naashoibitosaurus 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: Naashoibitosaurus is common in secondary-school and first-year university syllabi. It links to neighbouring topics Campanian dinosaurs, Dinosaur genera, Dinosaurs of the United States, so understanding it makes those chapters shorter.
In everyday life: Look for Naashoibitosaurus 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.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Naashoibitosaurus” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Naashoibitosaurus in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Naashoibitosaurus 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 Naashoibitosaurus out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Naashoibitosaurus in simple terms?

Why does Naashoibitosaurus 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 Naashoibitosaurus?

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 Naashoibitosaurus.