EXHIBIT 165
Dicraeosaurus hansemanni
Dicraeosaurus was a comparatively short-necked Tanzanian sauropod, distinguished by divided vertebral spines and a narrow feeding apparatus. [1]
TWO WAYS TO PICTURE THE PAST
Compare the evidence with the familiar movie image. The illustrations are not to a shared scale.
Berlin’s Dicraeosaurus hansemanni mount is a composite, including specimen m, other individuals’ bones and plaster restoration. Some replacements were modeled from D. sattleri. The photographed pose is an interpretation, not one intact fossil or evidence of living posture. [5]
Dicraeosaurus hansemanni Berlin mount · Interfase. Public domain. Resized proportionally and converted to WebP; no anatomical edits. The downloaded Commons source already includes any uploader revisions or crops; its selected license applies.
Skeletal mounts and drawings may restore missing parts; the caption identifies the displayed material.
Original cinematic interpretation of Dicraeosaurus. The short neck and bifid neural spines guide the silhouette; their external expression, covering and exact neck posture are reconstructed. Colors, lighting and scenery are artistic choices; this is not directly observed behavior. Lighting, coloration and scenery are artistic choices. This image does not document a fossil locality or behavior.
Original artwork · artistic interpretation.
Scientific view: source-informed reconstruction, credited paleoart or specimen-based imagery. Movie-style view: Original artistic interpretation. Reconstructions involve uncertainty.
MEET THE ANIMAL
Dicraeosaurus was a Late Jurassic sauropod from Tanzania with a comparatively short neck and divided vertebral spines. This profile centers on Dicraeosaurus hansemanni, keeping the later-occurring Dicraeosaurus sattleri separate. A genus can include different species and fossil horizons; combining them indiscriminately can create a body or size range that no actual individual possessed. [D1]
Scans of tooth-bearing bones reveal replacement teeth developing inside the jaws. Computed tomography, or CT, allows researchers to investigate structures hidden within a fossil. This helps them estimate tooth-replacement schedules rather than assuming that every tooth was replaced at exactly the same rate. The calculations concern how the feeding apparatus renewed itself, not a preserved record of individual meals. [D5]
Its relatively narrow snout has been used to propose selective feeding at intermediate heights. Selective browsing means choosing parts of vegetation rather than simply cropping everything within reach. This is a functional interpretation of skull shape and teeth. It does not identify the exact plants eaten, establish one fixed feeding height or show how the animal held its neck all day. [D7]
PREHISTORIC ANIMAL DOSSIER
The animal, the evidence, and the questions still open.
Berlin’s familiar mount combines bones and restoration. Dental CT and long-bone histology offer separate evidence about feeding and growth, while the animal’s social and reproductive habits remain uncertain. [D2] [D5] [D6]
Profile scope: Genus profile centered on Dicraeosaurus hansemanni, including type skeleton m, MB.R.4886. D. sattleri comes from a later Tendaguru horizon; its measurements are not blended into a species range. [D1]
Source supported identifies a description documented by the cited source. Inferred marks a reconstruction or functional estimate. Debated marks competing interpretations. Not established means the sources reviewed for this dossier do not support a firm conclusion; it does not mean a behavior never occurred.
A size reference is an estimate, not a population range. Nesting evidence does not by itself establish courtship, mate choice, or lifelong pairing.
13.2 m; displayed composite skeleton
The museum-origin register gives the Berlin mount’s length. Its assembled bones and restored portions are a display reference, not the measured body of one complete individual or a maximum adult length. [D4]
About 5.5 tonnes; later volume-density model
Table 10 models HMN m at 5,535 kg using restored volumes and regional densities. The 1999 contour model returned 12.8 tonnes. Different reconstruction assumptions produce these estimates; they are not a measured individual’s mass or a species range. [D3] [D2]
Selective plant browsing proposed
Snout shape and dental wear support relatively selective, mid-height feeding. They do not identify individual plant species, a fixed browsing height or stomach contents. [D7]
Late Jurassic Tendaguru, Tanzania
D. hansemanni occurs in the Middle Dinosaur Member; D. sattleri occurs in the later Upper Dinosaur Member. Keeping those horizons separate avoids treating species differences as one contemporary population. [D1]
Four-legged sauropod reconstruction
The assembled skeleton supports quadrupedal reconstruction. Replacement and modeled bones in the mount do not measure a living gait, speed or a unique habitual head position. [D2]
Rapid but unequal tooth replacement
CT-based estimates differ along the jaws: approximately 20 days for upper anterior replacement and 50 days for anterior lower teeth. These are modeled local rates, not one universal mouth-wide interval. [D5]
Growth-based maturation hypotheses
Long-bone histology suggests continued growth after an inferred maturation transition. That transition is not directly observed sexual maturity; securely assigned eggs, nests, embryos and parental behavior were not established here. [D6]
Not established here
The reviewed samples do not establish sexes or mate-choice displays. Growth differences and separate species should not be treated as observed courtship or a male–female pair. [D6] [D1]
Not established here
Bones from different individuals were combined in the museum mount. Their assembly documents reconstruction history rather than a fossilized social group, herd structure or coordinated behavior. [D2]
Sources and inspection notes for the claims in this profile.
THE STORY IN THE FOSSILS
CT reveals teeth developing inside the jaws, allowing replacement schedules to be estimated without assuming every tooth followed the same timetable. [5]
A mounted skeleton is an interpretation with a history. Here, substituted bones and a restored skull matter when comparing body size or reconstructing movement. [2]
The dossier identifies the scope of each reference estimate. A mount, an individual fossil and a species-wide adult range are different measurements. Comparison metrics remain unavailable where adult scope has not been established. Unknown does not mean zero.
Sources support the stated claims and scopes. Refer to the evidence notes for uncertainty.
KEEP EXPLORING
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Bajadasaurus pronuspinax
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Brachiosaurus altithorax
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