Forever young: locating mechanisms that relieve early mortality

Connor Bernard, Aldo Compagnoni and Roberto Salguero‐Gómez Senescence describes an organism’s physiological degradation with age, resulting in a higher risk of death and reduced reproductive performance over time. In recent years, many species across the Tree of Life have been identified that fail to conform to this pattern of senescing and its underlying classical theories. Certain species become more reproductive and less susceptible to death … Continue reading Forever young: locating mechanisms that relieve early mortality

Review: Assessing aging patterns for comparative analyses of mortality curves: Going beyond the use of maximum longevity

Victor Ronget & Jean-Michel Gaillard Actuarial senescence (i.e. the increase of mortality with age) is widespread throughout life but its strength varies a lot across species and even among populations. An increasing number of studies currently investigate the reasons for those differences in actuarial senescence. However, before trying to explain such differences, a reliable picture of patterns is required. Most studies performed to date relied … Continue reading Review: Assessing aging patterns for comparative analyses of mortality curves: Going beyond the use of maximum longevity

Coral reef with diver

Review: Senescence and sex

Matthias Galipaud and Hanna Kokko Anyone who has ever snorkelled above a coral reef has probably wondered how old a coral structure on a reef is. This is not an entirely easy question to answer. Corals reproduce sexually by sending off gametes into ocean water, in the hope that they find each other and fuse, but coral ‘growth’ is also a form of reproduction: new … Continue reading Review: Senescence and sex

Photo of Plantago lanceolata individual marked for senescence study. By: Deborah A. Roach

Review: Aging in plants is not always like aging in animals

Deborah A. Roach and Erin F. Smith Aging, also termed senescence, is manifest as declines in function and an increased risk of death as individuals get older.  All living organisms should experience some level of ‘wear and tear’, thus our theoretical expectation has been that all organisms should experience aging. One of our theories of aging, the Disposable Soma Theory, predicts that aging occurs because … Continue reading Review: Aging in plants is not always like aging in animals

Review: Why leveraging sex differences in immune tradeoffs may illuminate the evolution of senescence

Jessica Metcalf, Olivia Roth and Andrea Graham How might immune function shape aging, the increases in mortality and declines in fertility experienced at late ages by organisms across the tree of life? Classic evolutionary theory tells us that features that increase early life survival (or fertility) at the expense of later survival (or fertility) should spread within populations: such features will increase fitness simply as … Continue reading Review: Why leveraging sex differences in immune tradeoffs may illuminate the evolution of senescence

The untapped potential of reptile biodiversity for understanding how and why animals age

Luke A Hoekstra, Tonia S. Schwartz, Amanda M. Sparkman, David A. W. Miller, and Anne M. Bronikowski Reptiles include iconic examples of longevity, such as the Gálapagos tortoise, yet reptile aging is critically understudied. Compared to model organisms, we know little about how reptile populations age, or if and when reproduction declines. We review the existing literature on demographic aging in reptiles. We also examine … Continue reading The untapped potential of reptile biodiversity for understanding how and why animals age

Lasius species Queen Ant by gailhampshire. CC BY 2.0

The evolution of ageing in social species

Eric R. Lucas and Laurent Keller We know that social interactions are essential for humans to live a full and healthy life, but does social life increase health and lifespan in other species as a general rule? This question can be asked on two levels. First, at the level of the individual, do more socially-connected individuals live longer? Our review of the literature suggests that … Continue reading The evolution of ageing in social species

"elchato12 santacruz gen08" by doriana del sarto is licensed under CC BY-ND 2.0

Aging: it’s not just because reproducing wears us out!

Alan A. Cohen, Christophe Coste, Xiang-Yi Li, Salomé Bourg  and Samuel Pavard Why do we age? Since a given cell contains all the DNA necessary to manufacture an entire organism, why not just keep going indefinitely to reproduce more and maximize fitness? The currently accepted answer to that question largely relies on the idea of trade-offs: that by accepting some aging, we can increase reproduction … Continue reading Aging: it’s not just because reproducing wears us out!

Why does eating less make lab animals live longer? An evolutionary perspective.

Jenny C. Regan, Hannah Froy, Craig A. Walling, Joshua P. Moatt & Daniel H. Nussey, One of the most reliable ways to make lab animals, including worms, flies and mice, live longer and age slower is to reduce the amount of food they can eat. This so-called “dietary restriction” effect on aging is widely observed and is now known to be underpinned by signalling of … Continue reading Why does eating less make lab animals live longer? An evolutionary perspective.

Eco-evolutionary perspectives of the dynamic relationships linking senescence and cancer

Jean-François Lemaître, Samuel Pavard, Mathieu Giraudeau, Orsolya Vincze, Geordie Jennings, Rodrigo Hamede, Beata Ujvari & Frederic Thomas   In most animals, age-specific survival and reproductive probabilities decline with increasing age, a biological process known as senescence. While senescence is an almost ubiquitous process across the tree of life, senescence patterns differ widely among individuals, populations and species. Understanding factors shaping this variation is currently a … Continue reading Eco-evolutionary perspectives of the dynamic relationships linking senescence and cancer