The Aging Gap Between Species

Aging is a puzzle to solve. This process is traditionally studied in a couple of biological models like fruit flies, worms and mice. What all these species have in common is their fast aging. This is excellent for lab budgets. It is a great short-term strategy. Who has time to study species that live for decades? But lifespan differences among species are orders of magnitude larger than any lifespan variation achieved in the lab. This is the reason for which I studied countless information resources in an attempt to gather highly specialized research into one easy-to-follow book. I wanted to see the forest among the trees. I wanted to expose the aging gap between species in an easy-to-follow and logical sequence. This book is my attempt at doing just that. What are the mechanisms underlying the aging gap between species? I intentionally chose to write the answer to this question in plain English. Aging research is too important to hide it behind the closed doors of formal scientific jargon. This book could not have existed if green tea, libraries and the Internet were not invented. The amount of data I had to browse in order to keep the essential patterns is huge. Yet this book is not exhaustive. This is not a dry academic textbook. I tried to instill life in a topic that is hugely important for the extension of human lifespan. Only you can decide if I achieved this.

Contents

Finding the Forest Among the Trees

Being Reliable Counts

The Mathematics of Aging

The Speed of Senescence

Case Study: Aging in Fish

How to Estimate Chronological Age

Taking Life Slowly

On Temperature and Aging

Dormancy

The Housekeeping Problem

Case Study: Aging in Turtles

Intracellular Junk

Case Study: Aging in Crustaceans

Extracellular Junk

Case Study: Protein Quality Control

The Sweet Poison

Are Cell Membranes the Pacemakers of Metabolism?

Could Reproduction Set up the Pacemaker of Senescence?

The Segregation of Somatic and Germ Cells

Clonal Senescence Versus Mechanical Senescence

Same Species, Different Lifespans

Case Study: Eusocial Species

Case Study: Parasite/Free-Living Populations

Case Study: Island Versus Inland Populations

Hormones as Pacemakers of Senescence

Case Study: Low Hormone Levels in Long-lived Rodents

Is Aging a Form of Dehydration?

The Immune Pacemaker of Senescence

Innate Versus Adaptive Immunity

Senescent Cells

Case Study: Thymic Involution in Negligible Senescence Species

Reverse Engineering the Body

Case Study: Why Are Sponges Potentially Immortal?

Modular Growth and Aging

Case Study: Youth Is Forever Gone. Unless You Are a Hydra. Or an Immortal Jellyfish

Down The Neoteny Lane

Case Study: Neoteny in Amphibians

Case Study: Neoteny in Mammals

It's All About Neoteny

Does Aging Start When Growth Stops?

Case Study: Indeterminate Growth in Crustaceans

The Rate of Growth

Case Study: Aging in Bivalves

Is Telomerase The New Fountain of Youth?

Case Study: Same Species, Different Telomerase Expression

Telomerase Gene Therapy

Case Study: Sea Urchins

Perennial Plants and Their Regenerating Roots

Case Study: The Bristlecone Pine

Unitary Versus Colonial Organisms

Cancer

The Paradox of Peto

Case Study: Cancer in Long-Lived Species

The End

Acknowledgments

Bibliography