Fossil Focus: Coleoid cephalopods – the squid, cuttlefish and octopus

Fossil Focus: Coleoid cephalopods – the squid, cuttlefish and octopus

Fossil Focus
by Thomas Clements*1 What are coleoids? The coleoid cephalopods (Fig. 1), squids, cuttlefish and octopuses2, are an extremely diverse group of molluscs that inhabits every ocean on the planet. Ranging from the tiny but highly venomous blue-ringed octopus (Hapalochlaena) to the largest invertebrates on the planet, the giant and colossal squids (Architeuthis and Mesonychoteuthis respectively), coleoids are the dominant cephalopods in modern oceans. For humans, they are a vital dietary and economic resource and have an important role in our culture. Cephalopods have intrigued and been revered by humans from ancient times and, more recently, during the nineteenth and twentieth centuries, they became part of pop-culture. Stories of gargantuan poulpes attacking the submarine ‘Nautilus’ in Jule
Fossil Focus: Thalattosuchia

Fossil Focus: Thalattosuchia

Fossil Focus
by Mark T. Young*1, Sven Sachs2 & Pascal Abel3 Introduction: To most people, crocodilians are large-bodied carnivores that have been unchanged since the age of the dinosaurs. However, during their 230 million-year history, modern crocodilians and their extinct relatives evolved a stunning diversity of body plans, with many looking very different from those alive today (crocodiles, alligators, caimans and gharials). The first crocodylomorphs (the term used for living crocs and various fossil groups) are known from the Late Triassic Period, approximately 235 million to 237 million years ago. These animals lived on land and looked much more like a greyhound than a crocodile, with long legs and a skull that was deep like that of a meat-eating dinosaur, rather than flattened like that
Fossil Focus: Reimagining fossil cats

Fossil Focus: Reimagining fossil cats

Fossil Focus
by Andrew Cuff*1 Introduction: One of the biggest challenges palaeontologists face is how to reconstruct whole animals from their fossils. Most fossil remains are just bones, so how do we go from the bones to the soft tissues? For extinct species, we make deductions by looking at their nearest living relatives. This process is called the extant phylogenetic bracket (EPB). A good example of using the EPB is in reconstructing dinosaurs. Dinosaurs are alive today as their descendants, birds, but the non-avian dinosaurs we all know and love from Jurassic Park look very different from modern birds. Dinosaurs also have other living relatives: the crocodilians. Along with the dinosaurs and some other extinct groups, these are part of a group called the archosaurs (which means ‘ruling reptile
Patterns in Palaeontology — The earliest skeletons

Patterns in Palaeontology — The earliest skeletons

Patterns in Palaeontology
by Amelia Penny*1 Introduction and background The ability to build and maintain a skeleton is one of the major innovations in the history of life. During the Cambrian explosion, which began around 540 million years ago, diverse animal (metazoan) skeletons appeared suddenly in the fossil record. This is also when we first see evidence for predation, the ability to move around and most of the animal body plans we would recognize today. The ability to grow a resistant skeleton was a major factor in the evolutionary arms races of the Phanerozoic eon — the time since the Cambrian explosion — and it made possible the dizzying variety of shells, bones and teeth scattered throughout the Phanerozoic fossil record. But the origin of skeletons has a much deeper root, in the Proterozoic eon (2,500 m
Fossil Focus: Planktonic Foraminifera – Small Fossils, Big Impacts

Fossil Focus: Planktonic Foraminifera – Small Fossils, Big Impacts

Fossil Focus
by Janet Burke*1 Introduction and background: Although the microscopic creatures called planktonic foraminifera are still around today, most people have not heard of them. They don’t come to mind when the words "palaeontologist" or "fossil" are mentioned. They don’t have scales or claws, or big sharp teeth. They don’t even have mouths. If you were to visit the lab I work in, you wouldn’t see the specimens, just a row of compound microscopes and funny metal trays, slides and boxes of glass vials a little bigger than a pinky finger. If you look closer at those vials, each one contains hundreds upon hundreds of fossils, and each of those fossils has a story to tell. Etched into the nooks of its chambers and the very molecules of its calcite are facts about the ocean at a brief moment in tim
Perspectives — Palaeontology in 2017

Perspectives — Palaeontology in 2017

Perspectives
by The Palaeontology [online] editorial board*1 Introduction Every now and then at Palaeontology [online], we like to take a look at the world of palaeontology and reflect on what is happening in the field. Contrary to stereotypes, we believe that palaeontology and associated disciplines represent a fast-moving and exciting area of science. To highlight this, the members of the editorial board have each chosen a favourite paper from 2017. Picking just one paper was difficult for all of us, and it means that we have highlighted just five articles out of the many hundreds published in the past 12 months. Nevertheless, we hope that our choices reflect the breadth and depth of palaeobiological research in the twenty-first century. The papers include incredibly small and ancient invertebrates...
Fossil Focus: The ecology and evolution of the Lepospondyli

Fossil Focus: The ecology and evolution of the Lepospondyli

Fossil Focus
by Aodhán O'Gogain*1 Introduction and background During the Pennsylvanian subperiod (roughly 318 million to 299 million years ago), lush tropical rainforests covered much of what is now North America and Europe, but were then near Earth’s Equator. These tropical forests were teeming with animals, from 2-metre-long millipedes that scurried along among the roots to fish with fangs 10 centimetres in length that inhabited the associated rivers and estuaries. Living among these giants was a diverse group of small (less than 1 metre) vertebrates that resembled newts, lizards and snakes. These were the Lepospondyli, a sub-class of tetrapods that are characterized by having hourglass-shaped centrums, the central parts of their vertebrae. They had elongated, small bodies and short limbs, with one
Patterns in Palaeontology: The development of trilobites

Patterns in Palaeontology: The development of trilobites

Patterns in Palaeontology
by Lukáš Laibl*1 Introduction: Trilobites are an iconic group of ancient animals, with a fossil record that dates back more than 500 million years and consists of some 17,000 species. These extinct arthropods are characterized by a hard, mineralized exoskeleton, which greatly enhances their chances of being preserved as fossils. The exoskeleton is thought to have been mineralised soon after they hatched from eggs, and so we can find various growth stages of trilobites in the fossil record, including individuals less than half a millimetre long. That makes it possible to study the entire post-embryonic development (that is, the development after they hatch from the egg) of numerous species. This is important because work on the development of ancient organisms provides data crucial for ou
Education and Outreach: The history of dinosaur palaeoart

Education and Outreach: The history of dinosaur palaeoart

Education and Outreach
by Szymon Górnicki*1 Introduction: Non-avian dinosaurs are iconic animals that dominated life on land for 170 million years during the Mesozoic era, and have captured the imagination of scientists and non-scientists alike for as long as we have known about them. As a result, dinosaurs have also dominated palaeoart — artistic representations of past life. Palaeoart is closely linked to the science of palaeontology, resulting from the desire to reconstruct what extinct organisms looked like when they were alive, and is increasingly informed by the latest scientific discoveries. This article provides a brief historical account of dinosaur palaeoart, explaining how this work has changed as our understanding of the anatomy and biology of dinosaurs has improved. Scaled-up lizards: The first
Fossil Focus: The Archosaur Respiratory System — Or — Breathing Life into Dinosaurs

Fossil Focus: The Archosaur Respiratory System — Or — Breathing Life into Dinosaurs

Fossil Focus
by Robert Brocklehurst*1 Introduction and background Dinosaurs fascinate people more than almost any other group of fossil animals, and the general public is interested in many open questions on dinosaur biology. How fast could dinosaurs run? Were they warm blooded? If they had feathers, does that mean they could fly? These questions focus on dinosaur metabolism and movement, both of which are intimately linked with the respiratory system, because breathing — the ability to take in air, extract oxygen from it and then expel it from the body along with waste carbon dioxide— sets a fundamental upper limit on how much activity an organism is capable of. How did dinosaurs breathe? That’s probably not a question palaeontologists get asked as often as the others. Breathing is something we a