After the Dinosaurs: The Age of Mammals

by Donald R. Prothero

Perhaps nudged over the evolutionary cliff by a giant boloid striking the earth, the incredible and fascinating group of animals called dinosaurs became extinct some 65 million years ago (except for their feathered descendants). In their place evolved an enormous variety of land creatures, especially the mammals, which in their way were every bit as remarkable as their Mesozoic cousins.

The Age of Mammals, the Cenozoic Era, has never had its Jurassic Park, but it was an amazing time in earth's history, populated by a wonderful assortment of bizarre animals. The rapid evolution of thousands of species of mammals brought forth gigantic hornless rhinos, sabertooth cats, mastodonts and mammoths, and many other creatures--including our own ancestors.

Their story is part of a larger story of a world emerging from the greenhouse conditions of the Mesozoic, warming up dramatically about 55 million years ago, and then cooling rapidly so that 33 million years ago the glacial ice returned. The earth's vegetation went through equally dramatic changes, from tropical jungles in Montana and forests at the poles, to grasslands and savannas across the entire world. Life in the sea also underwent striking evolution reflecting global climate change, including the emergence of such creatures as giant sharks, seals, sea lions, dolphins, and whales.

After the Dinosaurs is a book for everyone who has an abiding fascination with the remarkable life of the past.

Genres: Science, Palaeontology, Nonfiction, Biology, Natural History, Nature, Evolution

362 pages, Hardcover

First published June 21, 2006

About the author

Donald R. Prothero is a Professor of Geology at Occidental College and Lecturer in Geobiology at the California Institute of Technology. He teaches Physical and Historical Geology, Sedimentary Geology, and Paleontology. His specialties are mammalian paleontology and magnetic stratigraphy of the Cenozoic. His current research focuses on the dating of the climatic changes that occurred between 30 and 40 million years ago, using the technique of magnetic stratigraphy. Dr. Prothero has been a Guggenheim and NSF Fellow, a Fellow of the Linnean Society, and in 1991 received the Schuchert Award of the Paleontological Society for outstanding paleontologist under the age of 40, the same award won by the renowned paleontologist Stephen Jay Gould. He has authored or co-edited numerous books, including Horns, Tusks, Hooves and Flippers: The Evolution of Hoofed Mammals, the best-selling textbook from McGraw-Hill, Evolution of the Earth, Evolution: What the Fossils Say & Why it Matters, Bringing Fossils to Life, After the Dinosaurs, and the textbook Sedimentary Geology. He is also a Technical Editor of the Journal of Paleontology.

Reviews

[Elentarri · Rating 3 out of 5]

An informative introductory book on the Age of Mammals meant for the interested lay-person or non-geologist/paleontologist. The book covers the end of the Age of Dinosaurs and the Age of Mammals until our current century. The author covers the changing climate, geography, flora and faunal species of each epoch (Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene) in separate chapters, accompanied by sketches, graphs, illustrations and a colour plate section. The brief section dealing with ancient hominins is a bit outdated (the book was published in 2006) and does not take into account new archaeological or genetic discoveries. However, this section is incredibly short, so not too important in this book. This book provides a good introduction to the Cenozoic Era, but does not deal with any particular topic in any particular depth. There is however, a list of further reading recommendations at the end of each chapter and a decent reference section. The author also tends to provide "lists" of species with obscure names in run-on sentences. This would have been ok if he was listing tigers, lions, elephants, crocodiles and hippos; instead we have "perissodactyls, artiodactyls, elephants, whales, uintatheres, tillodonts, arctostylopids, pantodonts, rodents, rabbits, hyaenodont creodonts, and advanced primates, or anthropoids" - which is rather disconcerting even with sketches of some of these creatures provided. Still, this book provides a nice overview of what was going on during the Age of Mammals.

[Zhelana · Rating 4 out of 5]

I imagine that it is hard to do elsewise, but large portions of this book read like lists of animals or plants i had never heard of before. I had no idea what they might look like or really anything about them. There were pictures of a few of them, and that helped, but often the picture was on one page and the description of the picture was on the next page so I had to go through awkwardly (I read the kindle version). It got better and better as time traveled forward but sections of it were always just lists of extinct animals or algae or something. Also, he went on this weird rant towards the beginning of the book about how a meteorite didn't kill the dinosaurs. All of the books I have read about dinosaurs have believed in this meteorite theory, including books written more recently than this one. I honestly think this is just a pet theory of his without science backing it? It also ended with a lecture on global warming suggesting that we're going to cause an ice age (which I think has been debunked, but I'm not as sure about this one). Anyway, it was a pretty interesting look at life for the last 65 million years and all of the fabulous designs mother nature has thrown out there the vast majority of which failed eventually. It also talked about what the climate was doing and even what the orbit of the earth was doing for that 65 million years. Overall, I think I'd recommend this book if you like biology or are interested in climate change.

[Daniel Morgan · Rating 4 out of 5]

Despite being 20 years old, this is a fantastic 5-star book. There are issues - which I will get to - but I am glad I read this, and I highly recommend it.

This is a breakdown of the entire Cenozoic Era, with a special emphasis on mammalian fauna. The book is organized into 9 chapters - 1 as an Intro, 1 on the K-T extinction, and then 7 chapters on the Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene.

The strongest feature of this book - and this is a feature of all good paleobiology books - is that it doesn't just focus on the star of the show. Prothero spends a great deal of ink explaining the evolution and diversification of mammals during the Cenozoic. However, this does not mean that he neglects the rest of the natural world.

Every chapter contains pages of information about paleogeography, paleoclimate, and the sort of geological character of the planet - it is important to know if we are in a tropical earth or an ice age; it is important to know if a region is tectonically stable or if there are massive flood basalts erupting across North America. Speaking of which, he does a fantastic job of differentiating the different continents - what is happening in South America vs Antarctica vs Europe vs . . . ? This explanation occurs in every chapter.

He also incorporates the broader ecological picture. What is the overall environment like - is this tropical Wyoming or glacial Canada? What are the unsung heroes of paleobiology - the plankton, mollusks, and plants - looking like during this particular Epoch? We can't really understand mammalian fauna without understanding the basic trophic levels. For that matter, what are the seas looking like? Is there anything interesting happening with birds, or lizards, or other organisms? All of this helps to set the mammals in a broader context, so that we can really appreciate what his happening in the world.

Finally, I love that differentiates so much both spatially and chronologically. Every chapter differentiates the continents and even different regions - for example, a fauna originating in India spreading across western Asia but NOT making it into China. In every chapter, ever part of the world gets its due, and this is not just a focus on the traditional centers of North America and Europe. Chronologically not only does every chapter focus on a different epoch, but Prothero actually explores the different internal Stages. And it's actually really cool to learn about the type localities for each stage - what makes the "Ypresian" Ypresian, and where is the Puercan from?

The book is full of comparative time scales displaying the mammalian ages vs the Stages for different regions, illustrations of important animals and features, maps, and photos. While I do wish that there were morphological diagrams - above all of teeth, which are crucial to mammalian biology - I do feel that the illustrations were sufficient at, well, illustrating the text. He also explains the mathematical science to us - such as the nitty-gritty details of Carbon and Oxygen isotopes - so that we can understand the evidence for how scientists reconstruct the climates of a bygone world.

Additionally, I appreciate Prothero's humility - he does not claim to have all the answers. Where there are (were) debates, he made sure to not only lay out both sides but even drop leading figures and books/papers (and the notes and bibliography are extensive).

Now, this book is almost 20 years old, and there a few items that I want to name as being . . . dubious:

1) There's an awful lot of skepticism regarding the Impact Theory's significance on the K-T Extinction. Not to detract from the Deccan Traps, but I think that skepticism has died off in the intervening two decades.

2) Around page 106, there's a discussion regarding Cetacea and their association to Mesonychidae and Artiodactyla. The prevailing science at the time was that Cetacea within Mesonychidae; to his credit, Prothero does mention that the very proponents of this theory are starting to suspect that Cetacea is within Artiodactyla, which in turn is a sister clade to Mesonychidae. In the Year of Our Lord 2025, Cetacea is now firmly within Artiodactyla and Mesonychidae isn't regarded as a particularly close relative. This isn't Prothero's fault, but just as a PSA that Cetacea's phylogeny has shifted.

3) Now this one is Prothero's Fault - there are about 5 pages dedicated to the Pliocene Great American Biotic Interchange (GABI).

On page 251-252 he writes "Relatively few South American natives made the trip North, with only eight genera (mostly ground sloths, glyptodonts, armadillos, and porcupines and capybaras) representing the "legions of the south" . . . according to Webb at least twenty-nine North American genera in fifteen families moved south, forming the "legions of the north" that soon came to dominate those of the south. These families included insectivores, rabbits, four families of rodents (pocket mice, field mice, pocket gophers, and squirrels), a huge wave of hoofed mammals (mastodonts, horses, camels, tapirs, peccaries, and deer) and nearly all the North American families of carnivorans (cats, sabertooths, weasels and skunks, dogs, bears, and more racoon relatives." Prothero even includes a helpful math showing the families, and from S.Am. to N.Am he lists 8 groups: ground sloths, glyptodonts, armadillos, anteaters, porcupines, opossums, capybaras, and notoungulates.

This is . . . nonsense. He lists the 18 mammalian families (standard cats and sabertooths are both in Felidae) from North America that migrated to South America.

But then South America he erroneously collapses everything together. "Anteaters" are actually 2 different families - Cyclopedidae and Myrmecophagidae. "Ground sloths" are 3 different families. He mentions Glyptodonts, but forgets the Pampatheriidae and Pachyarmatheriidae sister clades. He mentions Capybaras, but forgets the other 3 S.Am. rodent families of Echimyidae (spiny rats), Dasyproctidae (agoutis), and Cuniculidae (pacas). Being generous, the "8 genera" he stated are actually 16 different families.

But then most egregiously, he totally omits two very important groups. For as much as he talks about "ground sloths", he forgets that tree sloths exist and are very much present in North America as 2 distinct families. And worst of all, he somehow forgot that New World monkeys exist - specifically the spider monkeys (Atelidae) and the squirrel monkeys (Cebidae).

Summing this up, the Great Biotic Exchange actually has 18 North American families against 20 South American families - not 15 families North American against 8 South American genera. And a slip of phrase indicates the source of the error: "Peccaries were a Northern Hemisphere (mostly North American) group through most of their history, but now they are most common and diverse in Latin America, and barely make it into the dry deserts of the southwestern states" (p. 253).

In 1983, the paleobiologist Stephen Jay Gould published the book "Hen's Teeth and Horse's Toes", and in the essay "O Grave Where is Thy Victory" he explicitly names how a common error with the GABI is that Anglo-Americans keep forgetting that "Latin America" and "South America" are not the same thing. Apparently two decades later, Donald Prothero still forgot there's 3K miles between Panama and California for South American mammalian biota to wander about in.

Having concluded my GABI tirade, I do want to name two excellent points which Prothero makes, just to round out the final chapters.

1) He makes a convincing argument for why Climate should outweigh the Overkill hypothesis for most end-Pleistocence megafauan extinctions - as in, I was uncertain before I read his book, and now I am convinced regarding Climate.

2) He explores how Holecene climate change has intimately affected human civilizations around the world. Very few writers do this, and it did actually open my eyes to just how deeply climate has impacted the course of history.

Despite my notes, this is a fantastic, scholarly, and thorough book on the Cenozoic Era. I learned a lot, this is a great read, and I would both recommend this to anyone else and read this again soon. 5/5!

[Bill Leach · Rating 5 out of 5]

A fabulous book on life on Earth since the K-T boundary. Much broader than just the mammals, Prothero looks at each epoch and shows how the climate, the ecosystems, the flora and fauna changed with time. While the author describes the trends at the family and order level, he also includes many descriptions of specific species which no longer exist.

Many of the mammals described in the book have no common names. While the author uses common names where possible, many animals are now extinct and have so none making binomial nomenclature is necessary. It is worth getting to know the main orders to get a better idea of the changes over time.


Chapter 1 - Introduction

The science of correlating rock strata based upon fossils is termed biostratigraphy. Prothero provides a history of the development of the identification and naming of the strata making up the Cenozoic Era - the last 66 million years. Correlating these rocks around the world had been uncertain until deep sea drilling in the 1960's and 1970's revealed a continuous record of microfossils. Radiometric dating does not work for sedimentary rocks as the mineral crystals solidified long before the strata were deposited. Instead, dating of ash layers has been the key. As the Earth's magnetic field has switched thousands of times, magnetic stratigraphy can be used to date rocks as precisely as 100,000 years.

Chapter 2 - The End of the Dinosaurs

- there are currently three hypotheses for the cause of the K-T extinction: the Chicxulub bolide impact, the eruptions of the Deccan Traps, and dropping sea level
- the plankton are important in understanding the extinctions; being at the base of the food chain they are numerous and ubiquitous
- while the diatoms and dinoflagellates where unaffected, there was a major die out of the coccolithophorids (calcareous planktonic algae)
- the amoeba-like foraminiferans and radiolarians, which feed on diatoms and coccoliths, varied: the radiolarians and benthic foraminifera were fine, while the state of the planktonic foraminifera is less clear
- many marine animals show relatively little change at the K-T boundary, while many were in decline well before the K-T boundary
- on land, about 65% of all species survived the impact, there was significant extinction of the sharks, marsupials, lizards and dinosaurs, but bony fish, amphibians, turtles and champsosaurs survived
- looking at the animals that survived versus those that died out, the impact model fairs poorly; sea level change correlates well
- the author describes what is known of the evolution of birds from dinosaurs; of note is the fact that birds, pterosaurs and dinosaurs all have a joint between the first and second row of ankle bones: the cap on the end of a chicken drumstick is actually the first row of ankle bones
bird joint 41

Chapter 3 - The Paleocene

- most planktonic foraminifera died during the KT, but re-appeared shortly afterwards
- ten species of coccolithophorids survived the K-T, while thirty new coccolithophorids evolved
- most molluscs made it through, even at the genus level - the rudistid clams had died out during the late Cretaceous
- apparently only one species of coral survived due to the drop in plankton, but coral were diverse again by the late Paleocene
- the crash in the abundance of plankton led to only a few weedy species on a low productivity sea floor; however, diversity and productivity returned within a few thousand years
- the K/T extinction killed most of the large herbivores and carnivores, leaving a void into which the mammals evolved " in one of the most spectacular radiations ever documented."
- although placental mammals had evolved by 120 Ma, they had made little progress: by the end of the Cretaceus most mammals were marsupials and multituberculates - squirrel-like animals with rodent-like teeth most closely related to the monotremes
- by the end of the Paleocene (10-12 million years later), the Cretaceous placentals had given rise to all the orders of mammals including shrews, whales, rodents and bats
- common mammals where the archaic hoofed animals, the sheep-like pantodonts, multituberculates, early primates, seven families of small insectivorous mammals, the wolf-like creodonts, and the weasel-like miacids that had the carnassial teeth for shearing (a characteristic of all extant carnivores)
- a dramatic event occurred at the end of the Paleocene, now called the Initial Eocene Thermal Maximum, the produced a spike in carbon and subsequent warming; it is thought that ocean warming caused clathrates (frozen methane hydrates) along the continental shelves to melt, releasing huge volumes of carbon into the oceans and dramatically warming the globe through a greenhouse effect

Chapter 4 - The Eocene

the Early Eocene
- the early Eocene was very warm, with dense tropical vegetation throughout what are now the temperature regions of the world
- the most favoured theory for the cause of the warmth is a greenhouse effect due to the "huge methane burp" that terminated the Paleocene
- land bridges formed in the North Atlantic and the Bering areas that allowed much interchange of animals
- until the end of the Paleocene each continent had different fauna, but at the beginning of the Eocene interchange rearranged the fauna
- North America gained many odd-toed perissodactyls, including a variety of early horses, and even-toed artiodactyls in the form of small deer-like animals, which displace the archaic ungulates of the Paleocene
- North America also gained two advanced groups of lemur-like primates and the first creodonts (a now extinct order of carnivorous mammals)
- Europe also gained the perissodactyls and the artiodactyls; also the large herbaceous pantodonts from Asia and the first miacids (extinct carnivores)
- in Asia, perissodactyls became common, but not the artiodactyls; rodents came to dominate the small mammals
- the seas were warm and stable, with plankton and benthic foraminifera becoming incredibly diverse, the molluscs and the fish also thriving
- of note were the single celled nummulitids that secreted shells often centimetres across; some limestones are made almost entirely of them including much of the limestone used to make the Great Pyramids
- the extinction of the giant marine reptiles left the oceans without large predators, a role that was filled by the evolution of the whales
- discoveries in the 1980's and 1990's showed that the early whales (archaeocetes) evolved from mesonychids - an extinct family of even-toed hoofed carnivores

Eocene cooling
- continual cooling occurred throughout the Eocene, with the global temperature dropping by 12 degrees C.
- various theories as to the cause of the cooling include reduced carbon dioxide due to lower rates of seafloor spreading and the rapid uplift of the Himalayas; also changes in ocean circulation
- cooling caused a decline in the planktonic foraminifera, and the molluscs
- toward the end of the Eocene (37-38 Ma), a dramatic cooling event wiped out a huge number of warm-water taxa and fundamentally rearranged the marine faunas
- on land, the climate became more seasonal and semi-arid
- notable were the elephant-sized uintatheres, of unknown origin, and the brontotheres which evolved from dog-sized beasts to elephant-sized
- horses and artiodactyls diversified, crowding out the earlier herbivores

the late Eocene
- global temperatures warmed by 2 degrees C. during the last 3 million years of the Eocene
- while changes during the late Eocene have been attributed to impact events, detailed work shows the timing to be incorrect - impacts during that time had no significant effect
- the early whales (archaeocetes) were replaced by the odontocetes or toothed whales and the mysticetes or baleen whales

Chapter 5 - The Oligocene

the early Oligocene event
- the early Oligocene saw another sudden drop in temperature at about 33 Ma, now thought to be due to changes in ocean currents bringing cold water to the surface
- in North America, mean annual temperatures dropped by 8 - 12 degrees C. in less than a million years
- the cold greatly reduced the foraminifera and the molluscs
- as the mammals had experienced major adjustments in the late Eocene, changes due to the early Oligocene event were minimal
- there was a reduction in arboreal mammals - especially primates - and the replacement of leaf eaters with mixed feeders, reflecting the more arid climate
- in Asia, the fauna was even more arid-adapted with a great variety of rabbits, rodents and animals with high-crowned teeth
- Africa was still isolated and had an endemic fauna, the hyraxes being particularly common with some being rhino-sized

the late Oligocene
- cooling continued through the Oligocene with a major glaciation 30 Ma
- the change in animals was not great, likely as most had adapted to the cold in the late Eocene, but animal diversity was low
- in North America the oereodonts (an extinct family of cud-chewing artiodactyls) were common, a handful of three-toed horses were present, and new groups of rodents replaced earlier ones
- Asia was similar, but beardogs, weasels, civets and the first Asian dogs were the carnivores
- in South America, more high-crown toothed mammals reflect increasing savanna, the caviomorph rodents (chinchillas, porcupines) diversify into seven families, and the New World monkeys became established

Chapter 6 - The Miocene

the early Miocene
- temperatures warmed during the Miocene; the mean annual temperature of the Canadian Arctic was 11 degrees C.
- in the seas, benthic foraminifera and the molluscs prospered
- mass migrations reached a peak as land bridges became more usable
- North America received many immigrants from Asia including a rhinoceros and the bizarre Moropus which was built like a horse, but had long forelegs, short rear legs and claws
- dromomerycids - deer-like ruminants - pronghorns and dogs diversified and became common
- by the mid Miocene, the first true cat and the mastodonts arrived from Eurasia, while horses moved into Asia
- the land bridge between Europe and Africa formed, allowing many migrants into Africa including the first rhinos

Mid-Miocene climatic optimum
- a warm period occurred 14-16 Ma
- the foraminifera spread further north, molluscs proliferated, the toothed and baleen whales diversified, the pinnipeds appeared and the giant white shark (Carcharocles) appeared
- the shorelines off the North Pacific were inhabited by a semi-aquatic group called the desmostylians, which looked like a cross between a sea lion and a hippo

Mid to late Miocene cooling
- at 13-14 Ma, the south polar regions cooled suddenly causing the Antarctic ice cap to form
- it is thought that the cooling was caused by changes in ocean circulation of cold deep waters
- the rest of the Earth steadily cooled through the late Miocene, possibly due to increased weathering due to the uplift of the Himalayas
- the planktonic foraminifera, corals and molluscs all declined dramatically
- savannas developed, with a diverse set of animals akin to Africa today; however, "Instead of elephants, there were mastodonts; instead of hippos, hippo-like rhinos; instead of giraffes, long-necked camels; on so on."
- herbivores with low-crowned teeth were replaced by species with high-crowned teeth
- some families such as horses, giraffes, bears and dogs diversified greatly
- in Africa, the early primates diversified into the Old World monkeys
- about 6-7 Ma, the first hominids appear - slightly later, Ardipithecus appears whose leg structure shows that they walked upright
- between 5.6 and 5.8 Ma, Africa colliding with Europe resulted in blockages of the western Mediterranean; with no inflow from the ocean, the Mediterranean dried over a thousand years period, only to be refilled when the western barrier eroded; this happened around 40 times creating 2,000-3,000 metres of evaporites; this is known as the Messinian event

Chapter 7 - The Pliocene

early Pliocene
- warming in the early Pliocene occurred, probably due to changes in ocean circulation
- the land became warmer and moister, allowing mixed forests to grow
- in Europe, the sabertoothed cats had almost disappeared, with the first lynxes and lions showing up
- Australopithecus appears 3.9-4.2 Ma
- in Africa, drying caused grasslands to replace much of the forest, favouring our ground walking hominid ancestors

late Pliocene
- at the start of the late Pliocene, the Earth chilled quickly and ice caps formed on both poles; while the Antarctic had significant ice at times since 33 Ma, this was the first period in which the Arctic developed an ice cap
- it appears that this was due to the closure of the Panamanian isthmus which resulted in the formation of the thermohaline conveyor belt of currents that brought moisture to the Arctic which generated the snow and ice
- the closure of the Panamanian isthmus resulted in the Great American Interchange, where the isolated fauna of South America came in contact with the northern fauna - "one of the most extraordinary evolutionary experiments ever enacted in earth history"
- while only eight genera moved north, at least 29 genera moved south and dominated the earlier fauna including rodents, rabbits, many hoofed animals, cats and dogs
- many migrants from the north disappeared in the north and are often thought as native in South America, most notably the tapirs and camels (llamas, etc.)
- in Africa, the hominids diversified with Australopithecus africanus appearing, as well as the robust lineage Paranthropus
- the genus Homo appears, notably H. habilis

Chapter 8 - The Pleistocene
- Milutin Milankovich developed a theory wherein Earth is cyclically warmed and cooled as the Earth's orbit and tilt change
- by the 1960's thorium-protactinium dating of ancient coral terraces verified Milankovich's model
- the CLIMAP project has shown that there has been at least nineteen glacial-interglacial cycles in the last 700,000 years
- the Pleistocene was a time of ice ages; the last at 20,000 year ago covered virtually all of Canada with tundra to the south and the rest of the continent being mostly spruce forest
- the mammoths arrived from Africa; North American animals included the sabertoothed cat Smilodon, and the only surviving genus of horse, Equus, and a variety of camels and pronghorns
- immigrants from South America included giant sloths and armadillos
- at the end of the Pleistocene, the bison appear, having migrated from Asia
- the African fauna had stabilized and was similar to what is seen today
- hominids diversified, with H. erectus appearing and by 500,000 years ago having moved out of Africa into many parts of Eurasia; it's success is shown in that it changed little in brain size or body proportions over it's 1.8 million years of existence
- by about 300,000 years ago, Neanderthals became established in Europe and by 100,000 years ago, H. sapiens appeared
- gigantism was widespread amongst Pleistocene mammals, with giant beavers, ground sloths, camels, bison and American lion; Prothero suggests that giants were widespread throughout the Cenozoic, and only seem unusual as so few are left today
- the overkill hypothesis for the extinction of the megafauna has a number of weaknesses including a lack of evidence of kill sites, many animal groups that have been hunted did not die out (bison, deer), and that the die-out correlates better with the end of the last glacial some 10,000 years ago than the arrival of humans some 13,000 years ago

Chapter 9 - The Holocene
- this interglacial is considered the Holocene; interglacials have averaged 10,000 years while the last glacial peak was 20,000 years ago
- there is variation within the interglacial with the Climatic Optimum occurring 6,000-7,000 years ago, corresponding to the origin of many great civilizations including Egypt, Mesopotamia, and China; subsequent cooling and drought led to the downfall of the Mycenaeans and Hittites
- the Medieval Warm Period was followed by a cold fourteenth century culminating in the Little Ice Age
- Prothero finishes describing a number of disturbing trends including the sixth extinction, the population bomb and global warming

[William Yip · Rating 3 out of 5]

The book could have used another round of editing; there were extraneous or missing words, misspelled words, sentences with confusing meaning. The author used biased and dismissive language towards the meteor impact hypothesis even though he said there's not enough evidence for any hypothesis. The writing style and tone were very dry with list after list of species. That said, the content is very comprehensive, going through all the different eras and time periods after the dinosaurs went extinct and detailing all the species that came into being, flourished, and died out.

[Roy Van Den Brande · Rating 2 out of 5]

The content is ok, but it's just badly written.

[Jim D'Ambrosia · Rating 3 out of 5]

Mammalian history is amazingly rich, and the diversity of mammals is also amazing. The book did a good job of pointing this out. The book also serves to show that evolution isn't necessarily aiming at anything, and that mammals back then were not necessarily more primitive than those today.

The book and writing are competent, and this would be a good reference for the day I need to know about these things, but it was a slog. Any chapter in particular was fine, but reading one after another was ODTAA. This climate change and that; these species branch out and these go extinct. To be fair, I don't know how you avoid that, while covering all the ground.

[Link · Rating 3 out of 5]

This book contains lots of outdated information, I suggest you find something published more recently to get a better idea of current scientfic consensus.

I listened to the audiobook, so I cannot comment on the figures and photos that other people mention. The audiobook suffered from bad editing, for example a section in which the narrator misspoke and repeated a sentence that was not cut out. The narrator also chose a few uncommon pronunciations for taxonomic groups.

[Shelby · Rating 2 out of 5]

I see what a previous reviewer said about some of it seeming like he’s just listing animals without much description, and that he seemed to be trying to disprove the asteroid theory… really tho, if extinct mammalia are a special interest for you, you’ll already know most of the animals. The real issue here is that 20 years later, some of the science is out dated, and it’s particularly noticeable in the Neanderthal chapter…

[Kat Dixon · Rating 2 out of 5]

Probably the dullest book on prehistoric life I've ever stomached. Reads more like a dissertation than a book for lay readers. Not recommended—unless you're just really, really into that sort of thing.

[Eric Sullenberger · Rating 3 out of 5]

The introductory chapters and the beginning of most chapters are great overviews for newbies, but the book quickly gets into the technical. And although the audiobook is new, it is the original book from the early 2000s and is showing its age.

[George Polansky · Rating 4 out of 5]

A well written informative and entertaining book. I would have enjoyed it more if I retained more of my geology and biology courses. My Bad1

[Jeff Bursey · Rating 4 out of 5]

Clearly written, with many photographs, diagrams, charts, and color plates. Useful and comprehensive about the history of mammals and various extinction events along the way.

[Peter]

Too boring to continue

[Alice · Rating 3 out of 5]

Interesting.

[BVC · Rating 4 out of 5]

Parecchio dettagliato e ricco di foto, diagrammi e illustrazioni, questo testo di Prothero vorrebbe effettivamente essere un lavoro divulgativo ma c'è da dire che ciascuna pagina e ciascun capitolo/periodo geologico riporta liste di famiglie, ordini, specie animali e vegetali che a un lettore non avvezzo risulteranno assai facilmente aliene. Prothero avanza anche ipotesi sull'ecologia comportamentale di diversi gruppi animali, anche in relazione agli eventi planetari succedutisi (in particolare il focus è sugli eventi di estinzione di massa). In diverse sezioni discute di alcuni dei fattori di cui in paleontologia si tiene conto per effettuare una datazione, e molto spazio è dedicato anche alla descrizione dei mutamenti climatici.

Va tenuto presente che il testo è stato pubblicato nel 2006, per cui saranno varie le informazioni al suo interno imprecise o del tutto sbagliate rispetto a informazioni ed ipotesi odierne. Esempi rapidi: diverse volte gli intervalli temporali dei singoli periodi geologici sono errati; Gastornis viene presentato come un genere di volatili carnivoro, quando invece si nutrì più probabilmente di semi coriacei; il genere Batodonoides viene chiamato erroneamente Batonoides e, ancora erroneamente, collocato nel Paleocene (studi più recenti datano all'Eocene); i miacidi vengono classificati come antichi Carnivora ma a loro sono solo più probabilmente imparentati, rientrando comunque, come questi ultimi, tra i Carnivoramorfi.

Prothero, inoltre, all'inizio quasi si accanisce con l'ipotesi di Alvarez, la formulazione classica che vedrebbe attribuire l'estinzione di massa Cretaceo-Paleogene a un impatto asteroideo. Tra i motivi ci sarebbe la sopravvivenza delle creature d'acqua dolce (in particolare gli anfibi) che, invece, avrebbero dovuto essere decimate da eventuali piogge acide derivate dall'impatto. Si mostra invece gran sostenitore dell'ipotesi che vorrebbe attribuire le responsabilità di questa estinzione alle eruzioni di Deccan. Something something, Prothero sbaglia.

[Michael Holm · Rating 4 out of 5]

This work reviews the evolution of mammals after the dinosaurs died out at the end of the Cretaceous. The introduction explains fossils and their discovery. There is a chapter devoted to each of the epochs of the Cenozoic era. Many pictures and charts are provided for illustration which are very helpful. Evolution of mammals was driven by climate changes. Oxygen and carbon dioxide levels, salinity, glaciation, continental drift, sea levels and ocean currents determine environmental (temperature & moisture) changes. Vegetation adapts (evolves) to those changes. Herbivores adapt to changes in vegetation and temperatures. Carnivores adapt to herbivore changes. Omnivores have no choice but to also adapt. Primates were originally aboreal like some rodents such as squirrels. Humans came down from the trees to adapt to savannas. The last chapter considers how climate changes affected human history and the outlook for us now. All of these factors are explained and based upon scientific research and studies (frequently attributed).

The narrative reads like an article in Scientific American - a little academic but not too much. An introduction to some of the terms used to classify mammals such as brontotheres, tapiroids, entelodonts (based upon teeth) would have helped. As I realized that the value of the book was primarily its study of climate change, my interest grew. Temperatures were much warmer than we are experiencing now for a large part of the Cenozoic. This work looks at how mammals fared in such conditions. Animals tend to get larger in cold conditions. Dinosaurs did not have to cope with thermal regulation like mammals do. Perhaps reptiles will do well again in a hot climate. Our big problem now is over-population and how to produce enough food for everyone in a changing climate. And rapid extinction of many species.

Dr Donald Prothero has been a respected professor of geology for some time and written many books and scientific articles. His expertise is on the Cenozoic era and mammalian evolution. This is very illuminating study on an pertinent subject.

[Lou Cadle · Rating 5 out of 5]

Prothero is THE fossil rhino scientist in the world, but he's also wildly prolific as a writer. (Working as a paleontology assistant, I heard more tales of Prothero than of any other working paleontologist, mostly about his high energy levels, and as I cleaned a rhino jaw, his meticulous measurement in various articles were what I used to try and guess as the species of the thing I was uncovering.)

This is one of my go-to research books for writing my Dawn of Mammals series of novels. It was particularly useful for that because it is organized by epoch. But I also recommend the book to casual readers for the long chapter on why the Chixulub asteroid could not have, on its own, caused the extinction of dinosaurs. It's well documented and utterly convincing, and as I say, Prothero is not a nut, but one of the most respected (and brightest) paleontologists alive.

It's dense--not reading material for a teen or complete newcomer--and quite useful for my purposes.

[Mikael · Rating 3 out of 5]

I'm particularly interested in the time between the extinction of the dinosaurs and the rise of the humans, so this book seemed like just the thing for me. And it's interesting ... particularly if you like foraminiferans. They're little planktonic animals that fossilise easily and can be used to find out a great many things, about temperature in ages past, for instance. Interesting little critters in more ways than one. The problem, of course, is that this book isn't called After the Dinosaurs: The Age of Foraminiferans, which perhaps it should have been. The mammals of each era and epoch are counted off in a cursory way at the end of each chapter, and then there are pages and pages of text about and loving photos of ... foraminiferans.

Not boring, but clearly a case of false (or faulty) marketing.

[David Shapiro · Rating 5 out of 5]

I have been using this book as a research tool for my next graphic novel. I found this book to be very readable with useful pictures, illustrations and graphs. I highly recommend this book for fans of the past or anyone generally interested in earth science.