Late Ordovician
E402491
The Late Ordovician was the final subdivision of the Ordovician Period, marked by extensive marine biodiversity followed by one of the largest mass extinction events in Earth's history.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Late Ordovician canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T3899033 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Late Ordovician Context triple: [Ordovician Period, subdividedInto, Late Ordovician]
-
A.
Middle Ordovician
The Middle Ordovician is a subdivision of the Ordovician Period characterized by significant diversification of marine life and widespread shallow epicontinental seas.
-
B.
Late Devonian
The Late Devonian was the final epoch of the Devonian Period, marked by extensive reef collapse, major evolutionary changes in fish and early land plants, and several significant mass extinction events.
-
C.
Ordovician Period
The Ordovician Period was a Paleozoic era interval marked by extensive marine biodiversity, the diversification of early vertebrates and invertebrates, and ending with one of Earth's major mass extinction events.
-
D.
Early Devonian
The Early Devonian was the initial subdivision of the Devonian Period, marked by the diversification of early fishes and the spread of primitive vascular land plants across emerging terrestrial ecosystems.
-
E.
Devonian Period
The Devonian Period was a division of the Paleozoic Era characterized by the diversification of fish, the first significant colonization of land by plants and early tetrapods, and major reef-building in the oceans.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Late Ordovician Target entity description: The Late Ordovician was the final subdivision of the Ordovician Period, marked by extensive marine biodiversity followed by one of the largest mass extinction events in Earth's history.
-
A.
Middle Ordovician
The Middle Ordovician is a subdivision of the Ordovician Period characterized by significant diversification of marine life and widespread shallow epicontinental seas.
-
B.
Late Devonian
The Late Devonian was the final epoch of the Devonian Period, marked by extensive reef collapse, major evolutionary changes in fish and early land plants, and several significant mass extinction events.
-
C.
Ordovician Period
The Ordovician Period was a Paleozoic era interval marked by extensive marine biodiversity, the diversification of early vertebrates and invertebrates, and ending with one of Earth's major mass extinction events.
-
D.
Early Devonian
The Early Devonian was the initial subdivision of the Devonian Period, marked by the diversification of early fishes and the spread of primitive vascular land plants across emerging terrestrial ecosystems.
-
E.
Devonian Period
The Devonian Period was a division of the Paleozoic Era characterized by the diversification of fish, the first significant colonization of land by plants and early tetrapods, and major reef-building in the oceans.
- F. None of above. chosen
Statements (51)
| Predicate | Object |
|---|---|
| instanceOf |
geologic epoch
ⓘ
subdivision of the Ordovician Period ⓘ |
| associatedWith |
changes in ocean chemistry
ⓘ
changes in ocean circulation ⓘ continental configurations dominated by Gondwana ⓘ major reorganization of marine ecosystems ⓘ |
| bioticEffect |
collapse of many shallow-marine communities
ⓘ
selective extinction among warm-water taxa ⓘ turnover in reef-building organisms ⓘ |
| characterizedBy |
Late Ordovician mass extinction
ⓘ
diverse marine invertebrate faunas ⓘ extensive shallow epicontinental seas ⓘ global cooling ⓘ high marine biodiversity ⓘ large sea-level fall ⓘ major glaciation event ⓘ widespread carbonate platforms ⓘ |
| climateTrend | transition from greenhouse to icehouse conditions ⓘ |
| commonFossilGroup |
brachiopods
ⓘ
bryozoans ⓘ corals ⓘ crinoids ⓘ graptolites ⓘ nautiloid cephalopods ⓘ trilobites ⓘ |
| containsStage |
Hirnantian
ⓘ
Katian ⓘ Sandbian ⓘ |
| dominantLifeForm | marine invertebrates ⓘ |
| endTime | approximately 443.8 million years ago ⓘ |
| follows | Middle Ordovician ⓘ |
| glaciationCenter |
present-day North Africa
ⓘ
South America ⓘ
surface form:
present-day South America
|
| glaciationLocation |
Gondwana
ⓘ
surface form:
Gondwana supercontinent
|
| GSSPDefinedBy |
first appearance of the graptite Normalograptus extraordinarius (Hirnantian base)
ⓘ
first appearance of the graptolite Diplacanthograptus caudatus (Katian base) ⓘ first appearance of the graptolite Nemagraptus gracilis (Sandbian base) ⓘ |
| hasMajorEvent |
Gondwanan glaciation
ⓘ
Hirnantian glaciation ⓘ Late Ordovician mass extinction ⓘ |
| massExtinctionRank | one of the five largest Phanerozoic mass extinctions ⓘ |
| massExtinctionSeverity | eliminated an estimated 85 percent of marine species ⓘ |
| partOf | Ordovician Period ⓘ |
| positionInEon | Phanerozoic Eon ⓘ |
| positionInEra | Paleozoic Era ⓘ |
| positionInSystem | third and final series of the Ordovician System ⓘ |
| precedes |
Silurian
ⓘ
surface form:
Silurian Period
|
| seaLevelChange |
major regression during glacial maximum
ⓘ
subsequent transgression during deglaciation ⓘ |
| startTime | approximately 458.4 million years ago ⓘ |
| timeSpan | about 14.6 million years ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Late Ordovician Description of subject: The Late Ordovician was the final subdivision of the Ordovician Period, marked by extensive marine biodiversity followed by one of the largest mass extinction events in Earth's history.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.