Apatosaurus ajax

Apatosaurus is a genus of herbivorous sauropod dinosaur that lived in North America during the Late Jurassic period. Othniel Charles Marsh described and named the first-known species, Apatosaurus ajax, in 1877, and a second species, Apatosaurus louisae, was discovered and named by William H. Holland in 1916. Apatosaurus lived about 152 to 151 million years ago (mya), during the late Kimmeridgian to early Tithonian age, and are now known from fossils in the Morrison Formation of modern-day Colorado, Oklahoma, New Mexico, Wyoming, and Utah in the United States. Apatosaurus had an average length of 21–23 m (69–75 ft), and an average mass of 16.4–22.4 t. A few specimens indicate a maximum length of 11–30% greater than average and a mass of approximately 33 t.

Apatosaurus ajax

AbstractionBlue · CC BY-SA 4.0 · via Wikipedia/Commons. May be a photograph of a specimen, or an artist’s reconstruction — an interpretation of a skeleton, since colour and soft tissue are almost never preserved.

On record

Recorded, not inferred
Sits inside
ApatosaurusPBDB
Diet
herbivorePBDB, for Sauropoda
Life habit
ground dwelling, gregariousPBDB, for Sauropoda
Motility
actively mobilePBDB, for Sauropoda
Environment
terrestrialPBDB, for Sauropoda

Time the record covers

At most 12 million years on record.

Every occurrence read is dated to somewhere between 154.8 Mya and 143.1 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Late Jurassic — about 3 of 3 occurrencesLate JurassicEarly Cretaceous — about 0 of 3 occurrences155–154 Mya — about 0.1 occurrences154–154 Mya — about 0.1 occurrences154–154 Mya — about 0.1 occurrences154–153 Mya — about 0.1 occurrences153–153 Mya — about 0.1 occurrences153–152 Mya — about 0.1 occurrences152–152 Mya — about 0.1 occurrences152–151 Mya — about 0.1 occurrences151–151 Mya — about 0.1 occurrences151–151 Mya — about 0.1 occurrences151–150 Mya — about 0.1 occurrences150–150 Mya — about 0.1 occurrences150–149 Mya — about 0.1 occurrences149–149 Mya — about 0.1 occurrences149–149 Mya — about 0.1 occurrences149–148 Mya — about 0.1 occurrences148–148 Mya — about 0.1 occurrences148–147 Mya — about 0.1 occurrences147–147 Mya — about 0.1 occurrences147–146 Mya — about 0.1 occurrences146–146 Mya — about 0.1 occurrences146–146 Mya — about 0.1 occurrences146–145 Mya — about 0.1 occurrences145–145 Mya — about 0.1 occurrences145–144 Mya — about 0.1 occurrences144–144 Mya — about 0.1 occurrences144–143 Mya — about 0.1 occurrences143–143 Mya — about 0.1 occurrences155.3 Mya142.6 Mya

3 occurrences of Apatosaurus ajax on record, most of them in the Late Jurassic. Bar height is expected occurrences, not a count: each fossil is spread across the span it is dated to, so a tall narrow bar means tight dating and a low wide one means loose.

When

3 occurrences

These are dates about fossils, not the animal: the record can only begin after it arose and end before it died out, so either end may reach further. Shares are expected occurrences: a fossil dated to a span is counted partly in each period it straddles. More on what this infers.

Found in

1 formation

Morrison — 39.65°N, 105.19°W

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The named rock units Apatosaurus ajax has been recovered from, largest first. Drawn where the rock is now, not where it formed.

Apatosaurus ajax and its relatives

Late Jurassic

Where Apatosaurus ajax and its relatives were recorded in the Late Jurassic.

Found in the same rock

12 taxa

The Paleobiology Database records 3 sites for Apatosaurus ajax, and this reads all of them. The number is how many of those sites it was catalogued from too.

This is not a list of everything alive at the time. It is only what has come out of the same ground as this animal and been written down.

Entered from

3 references

Each of the 3 occurrences read was entered from one of these publications, ordered by how many each accounts for. This is not a search for papers mentioning the name. Entries link to doi.org where the Paleobiology Database holds an identifier, and to its own record where it does not. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.

Media and terms

Media content1

Picture of Apatosaurus ajax

Credit
AbstractionBlue
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

No 3D scan of Apatosaurus ajax was found in Sketchfab.

Smithsonian Open Access and MorphoSource were not reached for this taxon, so this list is what the others held rather than everything there is.

The description on this site

Licence
CC BY-SA 4.0

This is what the site found, which is not the same as what exists.

Keep going

What may have been alongside itApatosaurus through timeFormations of the Late JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Marsh 1877)