science

Oemleria janhartfordae

Oemleria janhartfordae 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 Oemleria janhartfordae rather than just read about it. In short: Oemleria janhartfordae is an extinct species of osoberry in the family Rosaceae. It was described from a single fossil flower found in the Okanagan Highlands of Washington state.

Key takeaways

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

Reference excerpt

Oemleria janhartfordae is an extinct species of osoberry in the family Rosaceae. It was described from a single fossil flower found in the Okanagan Highlands of Washington state. The species has been used as a dating point for both the rose family and the rose family tribe Exochordeae.

Distribution

The Oemleria janhartfordae fossil was recovered from a single site in the Eocene Okanagan Highlands of Central British Columbia and northeast central Washington state. The single described specimen is from the Klondike Mountain Formation in Northern Ferry County, Washington, being recovered from the "Boot Hill" site B4131 in Republic, Washington. Early estimates of the highlands sites ranged from Miocene to Eocene in age. The age of the Klondike Mountain Formation was debated for many years, with plant fossils suggesting a Late Oligocene or Early Miocene age, and the first descriptions of species from the area included them in the Middle Miocene Latah Formation. By the early 1960's the Klondike Mountain formation was thought to be late Oligocene in age. Potassium-argon radiometric dating of samples taken near the Tom Thumb mine in 1966 resulted in a tentative 55 million years old age. Further refinement of sample dating has yielded an approximately Early Eocene, Ypresian age, being radiometrically dated as 49.4 million years old. A 2003 report using dating of detrital zircon crystals with the tuffs of the Klondike Mountain Formation had been dated to 49.42 ± 0.54 million years ago, the youngest of the Okanagan Highlands sites, A 2021 report revised the possible oldest age to around 51.2 ± 0.1 million years ago based on isotopic data from zircon crystals.

History and classification During investigation of fossil Prunus flowers from the Klondike Mountain Formation, paleobotanists John Benedict, Melanie DeVore and Katherine Pigg discovered a fossil with a notably different morphology from the other specimens being studied. Based on examination of the flower Benedict, with DeVore and Pigg, formally described it in a 2011 International Journal of Plant Sciences peer-reviewed article in combination with the cherry relative Prunus cathybrownae. They designated the holotype specimen "SR 08-42-15 A&B" which was from the collections of the Stonerose Interpretive Center in Republic, Washington. The flower was collected by an interpretive center staff member who donated the specimens to Stonerose. Benedict, DeVore, and Pigg coined the species name janhartfordae as a matronym honoring Jan Hartford, a resident of Republic, in recognition of her dedicated collecting at Stonerose and the development of the customized core database essential for the operations of the center, "Stonerose Strata". The customized program tracks fossil specimens, the fossil collector data, and facilitates updates to the collectors on fossils in ongoing research. O. janhartfordae was used as last common ancestor for the tribe Exochordeae, though Jin et al note they feel the species should not have been included in Oemleria. They do not give specific details as to why they feel this other than that the age of the fossil itself is counter to some molecular dating results. It has also been included in fossil datasets for the dating of the family as a whole.

Description The single known flower is preserved in postanthesis and, based on the lack of petals and stamen, was starting to develop from flowering stage to fruiting stage. It is born on a 11 mm (7⁄16 in) long pedicel, that is narrow, 1 mm (1⁄16 in), and shows the scar from at least on basal bract. The flower has radial symmetry and the upper section of the gynoecium is 6 mm (1⁄4 in) wide. There are 5 pistils arranged in a circular pattern and fused at the bases. Each overall pistil is approximately 8 mm (5⁄16 in) tall, with a 5 mm (3⁄16 in) tall ovary topped by an 3 mm (1⁄8 in) tall style. The ovaries are enlarged with widths around 3 mm (1⁄8 in) while the styles are 0.5 mm (0 in) and the capping stigma are 1 mm (1⁄16 in) wide. The ellipsoid ovaries are asymmetric in profile, with the styles being slightly offset on the ovary tops and curve outwards from the flower center. The stigma has a bilobed shape and are flattened in profile. Around the bottom half of the ovaries is a partially preserved hypanthium.

Paleoenvironment

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with Oemleria janhartfordae

Start with the simplest possible case. Write down what Oemleria janhartfordae 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 Oemleria janhartfordae 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 Oemleria janhartfordae 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 Oemleria janhartfordae

In research: Oemleria janhartfordae 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 Oemleria janhartfordae 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: Oemleria janhartfordae is common in secondary-school and first-year university syllabi. It links to neighbouring topics Eocene plants of North America, Extinct flora of North America, Fossil record of plants, so understanding it makes those chapters shorter.
In everyday life: Look for Oemleria janhartfordae 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 Oemleria janhartfordae in 20 minutes

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Close the page and write down what Oemleria janhartfordae 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.
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Frequently asked questions

What is Oemleria janhartfordae in simple terms?

Oemleria janhartfordae is an extinct species of osoberry in the family Rosaceae. It was described from a single fossil flower found in the Okanagan Highlands of Washington state.

Why does Oemleria janhartfordae 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 Oemleria janhartfordae?

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 Oemleria janhartfordae.