Level 1 — Absolute Beginner
Scientists in Spain studied a very old fossil. It is a small crocodile. It lived 125 million years ago. It was about as big as a house cat.
A man found the fossil in 1902 in Catalonia, in Spain. The fossil went to a museum in Barcelona. It stayed there for more than one hundred years.
Now scientists used a special blue light. It is called ultraviolet light. Under this light they could see skin, small scales and lines on the tail.
The lines may be like stripes on animals today. Stripes help animals hide. This may be the oldest animal colour we know from this family.
- fossil
- the hard remains of an animal or plant from long ago
- crocodile
- a large reptile with strong jaws that lives in water
- museum
- a building where old or important things are kept and shown
- light
- the energy that lets us see things
- skin
- the outer cover of an animal's body
- scale
- one of the small flat plates on the skin of a fish or reptile
- tail
- the long part at the back of an animal
- hide
- to stay where others cannot see you
Level 2 — Elementary
A fossil that has been sitting in a Barcelona museum since the early twentieth century has just been read properly for the first time. It belongs to Montsecosuchus depereti, an extinct relative of modern crocodiles that lived about 125 million years ago in what is now Catalonia, Spain.
The skeleton is only about 50 centimetres long, so the living animal was roughly the size of a house cat. It was dug up in 1902 by an engineer and geologist named Lluis Maria Vidal at a limestone quarry in the Noguera region, and then it waited in a collection for more than a hundred years.
The new study used ultraviolet light, which makes some ancient tissues glow when ordinary light shows nothing. Under UV the researchers could see individual scales, cartilage, breathing structures, and small features inside some scales that may be sensory organs.
Modern crocodiles have similar organs in their skin. They sense touch, changes in water pressure, temperature and chemicals. The team also found alternating light and dark bands along the tail, which could be the oldest known colour pattern in a crocodile ancestor. The work was published in the Zoological Journal of the Linnean Society.
- extinct
- no longer existing anywhere on Earth
- skeleton
- all the bones of a body together
- quarry
- a place where stone is cut out of the ground
- limestone
- a soft pale rock often containing fossils
- tissue
- the material that the parts of a body are made of
- cartilage
- the strong flexible material in noses, ears and joints
- sensory organ
- a body part used to sense the world, such as an eye or ear
- band
- a stripe of colour across a surface
Level 3 — Intermediate
Some of the most productive fossil discoveries are made in museum drawers rather than in the field. Montsecosuchus depereti, a crocodylomorph roughly the size of a house cat that hunted in the tropical wetlands of Early Cretaceous Spain, was collected in 1902 by the engineer and geologist Lluis Maria Vidal from a lithographic limestone quarry in the Noguera region of Catalonia. It has been in the Museu de Ciencies Naturals de Barcelona ever since, and it has only now been examined for soft tissue.
The reason is technological. Under ordinary illumination the specimen reads as a flattened skeleton in pale rock. Under ultraviolet light, however, certain preserved organic residues fluoresce, and structures that had been invisible for a century separated themselves from the matrix. The team recorded individual scales, cartilage, respiratory structures and small features within some scales, concentrated around the neck, the limbs and the flanks of the trunk and tail.
Those features are the most suggestive part of the find. Living crocodiles carry integumentary sensory organs in comparable positions, structures that register touch and changes in water pressure while also responding to temperature and chemical signals. Finding candidates for the same equipment in a 125-million-year-old animal implies that this sensory toolkit is far older than the modern crocodile body plan.
The ultraviolet imaging also revealed alternating bands along the tail, which the researchers interpret as a possible camouflage pattern. If the interpretation holds, it would be the oldest documented coloration in any crocodylomorph. The paper appeared in the Zoological Journal of the Linnean Society, and its wider argument is methodological: long-studied specimens can still be new evidence once the imaging improves.
- specimen
- a single example of an animal or object used for study
- fluoresce
- to glow when hit by certain kinds of light
- matrix
- the rock that surrounds and holds a fossil
- flank
- the side of an animal's body between ribs and hip
- integumentary
- relating to the skin and its coverings
- camouflage
- colours or patterns that help an animal blend into its surroundings
- coloration
- the arrangement of colours on an animal
- methodological
- relating to the methods used to do research
Level 4 — Advanced
Palaeontology periodically rediscovers that its richest deposits are curatorial. The holotype of Montsecosuchus depereti, an atoposaurid crocodylomorph no larger than a domestic cat, was recovered in 1902 by the engineer and geologist Lluis Maria Vidal from the lithographic limestone of the Pedrera de Meia in Lleida, Catalonia, and has resided in the Museu de Ciencies Naturals de Barcelona through more than a century of intermittent scholarly attention. It was formally redescribed in 1990. Only now has anyone subjected it to a soft-tissue analysis, and the yield is considerable.
The enabling technique is ultraviolet-induced fluorescence, which exploits the differential response of residual organic compounds and mineral replacements against the surrounding carbonate matrix. What the method returned was not a single structure but an assemblage: articulated scale rows, cartilaginous elements, apparent respiratory architecture, and, within certain scales concentrated around the cervical region, the limbs and the lateral trunk and tail, small discrete features consistent with integumentary sensory organs.
The functional inference deserves stated caution, since morphology alone cannot confirm innervation. In extant crocodilians these organs are mechanoreceptive, registering touch and minute pressure differentials in water, with additional thermal and chemical sensitivity. If the Barremian structures are homologous, the sensory apparatus that makes a modern crocodile an effective ambush predator predates by a very long interval the skull and body proportions usually treated as the defining crocodilian adaptations, which relocates the innovation earlier in the lineage than the skeletal record alone would suggest.
The same imaging disclosed alternating light and dark banding along the tail, interpreted provisionally as disruptive patterning. Should that reading survive scrutiny, it constitutes the earliest documented coloration in Crocodylomorpha. Published in the Zoological Journal of the Linnean Society, the study makes an argument that extends well past one small reptile: a specimen catalogued, figured and cited for a hundred and twenty years was still carrying unread data, and the limiting factor was never the fossil.
- curatorial
- relating to the care and keeping of museum collections
- holotype
- the single specimen used to define a species
- fluorescence
- the glow given off by a material when energised by light
- assemblage
- a collection of different things found together
- innervation
- the supply of nerves to a part of the body
- mechanoreceptive
- able to detect touch, pressure or movement
- homologous
- sharing the same origin in evolution
- disruptive patterning
- markings that break up an animal's outline to hide it
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