To outsiders, phylogenetics, the study of the evolutionary relationships between organisms, must seem like quicksand: the landscape is ever-changing and what you thought was solid ground can turn into contested and unstable territory overnight. Even so, we are getting an ever-clearer picture. In no small part this is due to new methods: the rapid technological progress in DNA sequencing has now made it both feasible and affordable to sequence whole genomes (all of a cell’s DNA) instead of selected genes for many taxa. And when you can bring multiple lines of evidence – morphological, developmental, genetic, and palaeontological – to bear on the question of evolutionary relationships, the resulting family trees become better supported and more credible. That is exactly what Gonzalo Giribet and Gregory Edgecombe, both experts in invertebrate biology and palaeontology, have done here in The Invertebrate Tree of Life – a work of dizzying scope since 96% of all known species are invertebrates. They have synthesized a truly monstrous amount of research to give an overview of our current thinking on invertebrate phylogeny, writing a new benchmark reference work for students of invertebrates.
What does the deep ocean make you think of? An alien world right on our doorstep? The cradle of life? A global garbage dump? The lungs of the planet? Or the world’s most abused ecosystem? If I am to believe marine biologist Alex Rogers, the deep ocean is all of the above, and so much more. With three decades of research experience and scientific consultancy credits for the BBC series Blue Planet II under his belt, he knows what he is talking about and he knows how to talk about it. The Deep is an intensely captivating and urgent book that swings between wonder and horror.
When you think of an animal, you will most likely think of a vertebrate. Since we are animals with a backbone ourselves, it is not strange that that which is closest to us comes to mind first. But when and how did vertebrates evolve? To answer that question, Nature editor Henry Gee takes a good hard look at invertebrates, convincing the reader that they are not all equal. More than 20 years ago, Gee wrote Before the Backbone: Views on the Origin of the Vertebrates, which took a look at historical explanations for the origins of vertebrates. Which group of invertebrates is closest to us remains a topic of active research and Across the Bridge brings readers up to date with our current thinking.