When Environments Change

Can Algae save the world?

In today’s world with an increasing human footprint across the natural world, scientists believe we may be entering a sixth mass extinction. Fragmented habitats, introduction of invasive species, and climate change are just some of the factors leading to this mass extinction.  A lot of species still have yet to be recorded, so the number of extinctions of populations and species documented by scientists are likely to be large underestimates (Barnosky et al. 2011).  Climate change is one factor among many that is leading to the loss of biodiversity. Therefore, it is important for scientists to understand how populations respond to rapid environmental change. It is known that evolutionary history may affect risk of extinction within populations due to the accumulation of mutations, or pleiotropy. In one environment certain mutations will be favored, but in others they may have detrimental effects that reduce fitness, or reproductive success of a certain genotype in a population. (genotype being the genetic makeup of an individual) This would lower a population’s ability to withstand environmental change due to the accumulation of mutations which aren’t suited for the new environment. (MacLean et al. 2004) Understanding evolutionary history is crucial for understanding how populations will respond to environmental change caused by climate change. In the October edition of the Journal of Evolutionary Biology there was a study looking at how evolutionary history affects extinction probability.  Its title is “The effect of selection history on extinction risk during severe environmental change”. This study looked at how the extinction risk of populations of the green algae Chlamydomonas reinhardtii changed with various stressful environments (Lachapelle et al. 2017).

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Coral Reefs and Phenotypic Plasticity: Responses to a Changing Climate

Introduction

Coral reefs are known as pristine locations, and the ability of the coral making them up to create environments supporting myriads of fish species is astounding. Comparisons between corals ability to create a niche for complex and diverse ecosystems has been compared to that of rain forests on land, with almost a third of marine fish being found, despite covering less than 1% of the ocean bed (Adey 1998). In fact, many of the species that live within these reefs owe survival to coral health (Komyakova et al 2013). However, the home of Nemo and Ariel has been under recent threat over the years, due to climate change and ocean acidification (Hoegh-Guldberg et a. 2007). Just this last year alone, the great barrier reef saw the worst coral bleaching, thanks to rising water temperatures (Griffith 2016).  While exploration of ways to change the impact we are having on corals, and therefore the impact on the reefs ecological webs as a whole, interest has also developed in what the corals responses to these changes in their environment have been (Putnam et al. 2016). The value of this data provides an extreme example of phenotypic plasticity, the ability of an organism to respond to its environmental conditions. Continue reading “Coral Reefs and Phenotypic Plasticity: Responses to a Changing Climate”

Evolutionary advantage of learning to cope with change

Background

Whether migratory birds will respond successfully to rapid climate change is unclear.  Birds migrate to take advantage of seasonal peaks in resource availability: Food and habitat become abundant quickly during summer at northern latitudes, but decline quickly in the fall.  Timely arrival on the summer range is vital for many species (Alerstam and Hedenström 1998). Continue reading “Evolutionary advantage of learning to cope with change”

Great Tits and Climate Change: An Experiment to Transform Current Prediction Models

 

Great tit feeding on caterpillar. Credit Kateimi Flickr user.

Background:

Timing is everything for bringing new life into the natural world. Every year, species such as the great tit (Parus major), one of the many song birds found on the British Isles, rely on abundant food to be able to provide enough nutrients for their growing young. The presence of this food is the result of a large cascade—like a line of dominos—that begin with the smallest of microorganisms responding to environmental factors such as temperature and salt concentration. If the timing of one of these falling dominoes is slightly off, many organisms further down the line suffer and may be unable to find food at the most critical times of early offspring growth. Two particular organisms that share the same line of dominoes as the great tit are the pendunculate oak (Quercus robur) and the various caterpillars which feed on the oak’s leaves. [3] Continue reading “Great Tits and Climate Change: An Experiment to Transform Current Prediction Models”