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Patterns in Palaeontology

Patterns in Palaeontology: Palaeoproteomics

Patterns in Palaeontology: Palaeoproteomics

Patterns in Palaeontology
by Caitlin Colleary*1 Introduction: The fossil record is our only direct window to the history of life on Earth. The ability to find and study the remains of animals, plants and other organisms that lived millions of years ago is extraordinary, and as technology has improved over the past few decades, scientists have realized that fossils contain more information about the stories of extinct life forms than even Charles Darwin could have imagined. Biomolecules (such as DNA, proteins and lipids) that make up modern animals contain information about how their bodies work (physiology — that is, physical and chemical functions), relationships to other animals and their evolutionary histories. With the advances in analytical tools such as high-resolution mass spectroscopy, the study of biomol
Patterns in Palaeontology: From giants to dwarfs – Estimating the body mass of extinct species

Patterns in Palaeontology: From giants to dwarfs – Estimating the body mass of extinct species

Patterns in Palaeontology
by Charlotte Brassey1 Introduction Body mass is so fundamental to an organism that it is often overlooked, yet it has considerable importance in animal biology. It is, quite literally, the amount of matter making up an individual. On a day-to-day basis, we encounter values for body mass as we step onto our bathroom scales and are encouraged to maintain a healthy weight (not too heavy or too light). Veterinarians are interested in body mass for much the same reason: the weight of an animal can provide an indication of its health and is commonly used to plan medical treatments. Body mass is also tied to an animal’s physiology (including speed of metabolism and length of pregnancy), ecology (diet, home-range size) and behaviour (social status, aggression). For these reasons, zoologists are
Patterns in Palaeontology: A story of vision

Patterns in Palaeontology: A story of vision

Patterns in Palaeontology
by James Fleming*1 Introduction: Photoreception, the ability to perceive light, is a sense shared by many living organisms on Earth. However, only some can take the step beyond merely detecting light levels, and generate an image. Humans are among the animals that have image-forming vision, and are able to see in colour in the day (polychromatic diurnal vision) and in black and white at night (monochromatic nocturnal vision) — the shades of colour that we pick up on an evening out trigger our diurnal receptors at very low levels. However, this is not the only way in which animals can see the world around them. Some species, such as whales and dolphins, can see only monochromatically no matter the time of day, while others see in colour no matter how dark it gets! The elephant hawk-mot
Patterns in Palaeontology: How and why did the arthropod shed its skin? Moulting in living and fossil arthropods

Patterns in Palaeontology: How and why did the arthropod shed its skin? Moulting in living and fossil arthropods

Patterns in Palaeontology
by Harriet B. Drage*1 Introduction: Arthropods are one of the most successful groups of animals, in the present day and the fossil record. There are more than 1 million described arthropod species, and it has been estimated that there are at least 5 million more undescribed alive today (Fig. 1). This makes up more than 80% of all known animal species! Arthropods also have an extremely diverse fossil record, extending back to the Cambrian Explosion 541 million years ago. For much of the Palaeozoic era (541 million to 252 million years ago), arthropods dominated marine ecosystems, and they have been significant components of all environments since then. The phylum Arthropoda encompasses insects (Hexapoda), crustaceans (such as shrimps and lobsters) and arachnids (such as spiders), a...

Patterns in Palaeontology: Palaeogenomics

Patterns in Palaeontology
by Jeffrey R. Thompson*1 Introduction: Palaeontology is truly a science of the twenty-first century. Palaeontologists are no longer concerned only with fossils, but also with topics such as genetics, developmental biology and chemistry — although most of us can’t resist digging around in the dirt from time to time! You are almost as likely to find a palaeontology graduate student in a class on molecular biology as in one on stratigraphy. This is because, in recent years, the integration of fossil, developmental and genetic data has fast become one of the most promising ways to study the patterns and processes of evolution. At this point, it may be helpful to introduce some of the sources of information that palaeontologists use to address large-scale evolutionary questions. Molecular

Patterns in Palaeontology: Palaeoart – fossil fantasies or recreating lost reality?

Patterns in Palaeontology
by Mark P. Witton*1 Introduction: Illustrations, sculptures and animations of fossil organisms and the world around them are mainstays of palaeontology. Such restorations, known as palaeoart, are more important than they may at first seem: they help to communicate palaeontological ideas across age and language barriers; have inspired generations of scientists; and have provided the foundation of an international industry of palaeontology-themed merchandise and media worth hundreds of millions of pounds. Due to its increasing prominence and popularity, palaeoart is routinely scrutinized by scientists and the public alike. How can we infer so much about the postures, soft tissues, colours and behaviour of extinct animals when fossil skeletons — be they shells, bones or carapaces — are all

Patterns in Palaeontology: The latitudinal biodiversity gradient

Patterns in Palaeontology
by Philip D. Mannion*1 Introduction: Today, most living species are found in the tropics, the region of the Earth that surrounds the Equator. Species numbers, a measure of biodiversity, decline towards both the North and South poles (Fig. 1). This is known as the latitudinal biodiversity gradient (LBG), and it is the dominant ecological pattern on Earth today. Although there are exceptions to the rule, including high-latitude peaks in diversity of many marine or coastal vertebrates (including seals and albatrosses), the LBG describes the distribution of species diversity for the vast majority of animals and plants, both on land and in the sea, and in the Northern and Southern hemispheres. Understanding the causes and evolution of the LBG helps researchers to explain present-day geograp...

Patterns In Palaeontology: Trends of body-size evolution in the fossil record – a growing field

Patterns in Palaeontology
by Mark A. Bell*1 Introduction: The body size of an animal is often considered the most important part of its biology. Large body size brings many advantages, which can include better ability to capture prey, success in evading predators, intelligence, longevity and reproductive success; it also makes a greater range of resources available. A larger animal has a lower surface area to volume ratio than a smaller animal, which results in less heat loss to the surroundings, allowing it to remain warmer for longer in a cold environment. However, one major disadvantage is that larger organisms are, in general, more specialized, and can require more food for example. This can put species at higher risk of extinction caused by rapid environmental change. Since the work of nineteenth-century ...

Patterns in palaeontology: An introduction to ancient DNA

Patterns in Palaeontology
By Peter D. Heintzman*1 Introduction: Deoxyribonucleic acid, or DNA for short, is the magical molecule that encodes instructions on how to build organisms, and has been doing so successfully for at least the past 2.5 billion years. Although its function has remained constant throughout this time, the instructions themselves have been slowly modified and upgraded to cope with the changing demands of organisms and the environments in which they live. A modification to DNA is called a mutation, and it is through mutations that we are able to track how organisms have changed, or evolved, through time. In all multicellular organisms, there are two major types of DNA: mitochondrial (mtDNA) and nuclear (nuDNA) (Fig. 1). These have different histories and can therefore tell us different thing...

Patterns in Palaeontology: Why the thunder lizard was really the deceptive lizard.

Patterns in Palaeontology
by Chloe Marquart1 When I tell the average stranger that I'm a palaeontologist, the first question that I'm inevitably asked is: "Like Ross from Friends?" The second is: "Have you named any dinosaurs?" The naming of fossils is actually a very small part of the work that palaeontologists do, but it often garners the most attention from the press and public. It can be difficult for people to understand how scientists can suddenly decide that a well-known, often iconic name has never 'existed' - in a scientific sense, at least. Many grown adults still mourn the loss of their beloved Brontosaurus (more on him later), and in the past few years, campaigns were begun to ‘Save Triceratops’ when it was declared that this dinosaur and Torosaurus might be the same animal (Fig. 2). Although