Tag: adaptation

More Fun with Not-so-Dumb Organisms and the U.S. National Assessment of Climate Change

Last time around, we brought forth evidence against organismal “dumbness”—the notion that species found only in defined climatic environments will go extinct if the climate changes beyond their range. We picked on cute little Nemo, and “found,” much like in the animation, that his kind (Amphiprion ocellaris) could actually survive far beyond their somewhat circumscribed tropical reef climate.

The key was the notion of plasticity—the concept that, despite being linked to a fixed genetic compliment, or genotype, the products of those genes (the “phenotype”) changed along with the environment, allowing organisms some degree of insurance against climate change. How this comes about through evolution remains a mystery, though we may occasionally indulge in a bit of high speculation.

“Science,” according to the late, great philosopher Karl Popper, is comprised of theories that are capable of making what he called “difficult predictions.” The notion that gravity bends light would be one of those made by relativity, and it was shown to be true by Sir Arthur Eddington in the 1919 total solar eclipse. It just happened to be in totality in the Pleiades star cluster (also the corporate logo of Subaru), and, sure enough, the stars closest to the eclipsed sun’s limb apparently moved towards it when compared to their “normal” positions.

So we have been interested in a truly difficult test of phenotypic plasticity, and we think we found one.

How about a clam that lives in the bottom of the great Southern Ocean surrounding Antarctica? Specifically, the burrowing clam Laternula elliptica. According to a recent (2017) paper by Catherine Waller of the University of Hull (in the, perhaps temporarily, United Kingdom) “75 percent of the recorded specimens [of L. elliptica] are from localities shallower than 100 m,” where the populations are exposed to “low and stable water temperatures in the range of -1.9 to +1.8 °C” (the remaining 25 percent inhabit cooler waters of the continental slope down to ~700m).

Laternula elliptica

Laternula elliptica

A True Fish Story: Adaptive Responses to Global Warming

The simplistic notion that organisms are “dumb” when it comes to changing environments goes like this: Species X lives in a relatively stable environment and with a certain defined range of temperature. So, if the temperature changes enough, species X will go extinct.

In resuming our series on biological adaptation to environmental change, we are going to be looking in depth at the evolutionary and environmental nuances that—with some limits—invalidate the simple point of view. And, in doing so, we will discover important implications for environmental and climate-related policies.

We begin with revolutionary classic in evolutionary biology published in 1984 by Peter Hochachka and George Somero called “Biochemical Adaptation.” It summarized and expanded on much of their earlier work on what they called “phenotypic plasticity”.

You Ought to Have a Look: Climate Fretting and Why It’s Unjustified

You Ought to Have a Look is a regular feature from the Center for the Study of Science. While this section will feature all of the areas of interest that we are emphasizing, the prominence of the climate issue is driving a tremendous amount of web traffic. Here we post a few of the best in recent days, along with our color commentary.

While “climate fretting” has become a pastime for some—even more so now with President-elect Trump’s plans to disassemble much of President Obama’s “I’ve Got a Pen and I’ve Got a Phone”-based Climate Action Plan—climate reality tells a much different story.

For example, a new analysis by Manhattan Institute’s (and YOTHAL favorite) Oren Cass looks into the comparative costs of climate changevs. climate action. His report, “Climate Costs in Context” is concise and to-the-point, and finds that while climate change will impart an economic cost, it is manageable and small in comparison to the price of actively trying to mitigate it. Here’s Oren’s abstract:

There is a consensus among climate scientists that human activity is contributing to climate change. However, claims that rising temperatures pose an existential threat to the human race or modern civilization are not well supported by climate science or economics; to the contrary, they are every bit as far from the mainstream as claims that climate change is not occurring or that it will be beneficial. Analyses consistently show that the costs of climate change are real but manageable. For instance, the prosperity that the world might achieve in 2100 without climate change may instead be delayed until 2102. [emphasis added]

In other words, the economic impacts of climate change aren’t something worth fretting over.

On The Bright Side: Declining Deaths Due to Hot and Cold Temperatures in Hong Kong

Global warming theory predicts increased mortality due to global warming, but observations frequently suggest the opposite. The newest case-in-point comes from a study by Chau and Woo (2015).

Setting the stage for their enlightening new study, the pair of researchers note there is a growing concern about the potential impacts of global warming on human mortality, where some researchers estimate future increases in heat-related deaths will outnumber future decreases in cold-related deaths. In a test of this hypothesis, the two Chinese scientists examined summer (June-August) versus winter (December-February) excess mortality trends among the older population (65 years and older) of Hong Kong citizens over the 35-year period 1976-2010. This was accomplished through the performance of statistical analyses that searched for relationships between various measures of extreme meteorological data and recorded deaths due to cardiovascular and respiratory-related causes. And what did those analyses reveal?

With respect to the weather, Chau and Woo report there was an average rise in mean temperature of “0.15°C per decade in 1947–2013 and an increase of 0.20°C per decade in 1984–2013.” They also note that over the 35-year period of their analysis “winter became less stressful” with fewer extreme cold spells. Summers, on the other hand, became “more stressful as the number of Hot Nights in summer increased by 0.3 days per year and the number of summer days with very high humidity (daily relative humidity over 93%) increased by 0.1 days per year.” Given such observations it would be expected—under global warming theory—that cold-related deaths should have declined and heat-related deaths should have increased across the length of the record. But did they?

Warming-Assisted Rapid Evolution of a Parasitic Host

In 1980, heated water from a nuclear power plant in Forsmark, Sweden (60.42°N, 18.17°E) began to be discharged into Biotest Lake, an artificial semi-enclosed lake in the Baltic Sea created in 1977 that is adjacent to the power plant and covers an area of 0.9 km2 with a mean depth of 2.5 m. The heated water has raised the temperature of the lake by 6-10°C compared to the surrounding Baltic Sea, but aside from this temperature difference, the physical conditions between the lake and the sea are very similar.

A few years after the power plant began operation, scientists conducted a study to determine the effect of the lake’s increased temperatures on the host-parasite dynamics between a fish parasite, the eyefluke (Diplostomum baeri), and its intermediate host, European perch (Perca fluviatilis). That analysis, performed in 1986 and 1987, revealed that perch in Biotest Lake experienced a higher degree of parasite infection compared to perch living in the cooler confines of the surrounding Baltic Sea (Höglund and Thulin, 1990), which finding is consistent with climate alarmist concerns that rising temperatures may lead to an increase in infectious diseases.

Fast forward to the present, however, and a much different ending to the story is observed.

Nearly three decades later, Mateos-Gonzales et al. (2015) returned to Biotest Lake and reexamined the very same host-parasite dynamic to learn what, if anything, had changed in the intervening time period. According to the team of researchers, Biotest Lake “provides an excellent opportunity to study the effect of a drastically changed environmental factor, water temperature, on the evolution of host-parasite interactions, in a single population recently split into two.” Specifically, it was their aim “to examine if the altered conditions have produced a change in prevalence and/or intensity of infection, and if these potential variations in infection have led to (or might have been caused by) a difference in parasite resistance.”

Response to Heat Stress in the United States: Are More Dying or Are More Adapting?

One of the concerns expressed by the United Nations Intergovernmental Panel on Climate Change (IPCC) with respect to the potential impacts of CO2-induced global warming is an increase in the number of heat related deaths, which they predict should occur in response to enhanced summertime temperature variability and more extreme heat waves, particularly among the elderly.

Is this really the case? A new paper published by Bobb et al. (2014) in the scientific journal Environmental Health Perspectives provides an answer. 

In prefacing their work the team of four U.S. researchers writes “increasing temperatures are anticipated to have profound health impacts,” but they say “little is known about the extent to which the population may be adapting.” Therefore, they decided to examine “the hypothesis that if adaptation is occurring, then heat-related mortality would be deceasing over time.”

To accomplish this objective, Bobb et al. used “a national database of daily weather, air pollution, and age-stratified mortality rates for 105 U.S. cities (covering 106 million people) during the summers of 1987-2005,” employing “time-varying coefficient regression models and Bayesian hierarchical models” to estimate “city-specific, regional, and national temporal trends in heat-related mortality and to identify factors that might explain variation across cities.”

With respect to their findings, Bobb et al. state “on average across cities, the number of deaths (per 1,000 deaths) attributable to each 10°F increase in same-day temperature decreased from 51 in 1987 to 19 in 2005” (see Figure 1). Furthermore, they report “this decline was largest among those ≥ 75 years of age, in northern regions, and in cities with cooler climates.”  In addition, they write “although central air conditioning (AC) prevalence has increased, we did not find statistically significant evidence of larger temporal declines among cities with larger increases in AC prevalence.”

Figure 1. The number of excess U.S. deaths (per 1,000) attributable to each 10°F increase in the same day’s summer temperature over the period 1987 to 2005. Adapted from Bobb et al. (2014).

Figure 1. The number of excess U.S. deaths (per 1,000) attributable to each 10°F increase in the same day’s summer temperature over the period 1987 to 2005. Adapted from Bobb et al. (2014).

Based on these findings, Bobb et al. conclude the U.S. population has, “become more resilient to heat over time”—in this case from 1987 to 2005—led by the country’s astute senior citizens. This discovery, coupled with many other similar findings from all across the world (Idso et al., 2014), adds yet another nail in the coffin of failed IPCC projections of increased heat related mortality in response to the so-called unprecedented warming of the past few decades. Perhaps it is high time for all the other apocalyptic projections of the global warming movement to be removed from life support, as they are each equally failing in comparisons with real world data.

References

Bobb, J.F., Peng, R.D., Bell, M.L. and Dominici, F. 2014. Heat-related mortality and adaptation to heat in the United States. Environmental Health Perspectives 122: 811-816.

Idso, C.D, Idso, S.B., Carter, R.M. and Singer, S.F. (Eds.) 2014. Climate Change Reconsidered II: Biological Impacts. Chicago, IL: The Heartland Institute.

The Adaptive Response of Salmon to Global Warming

…the extinction horrors of climate change may be a “fish story”

Perhaps the myth-iest chestnut in the scary global warming meme is that our dear earth’s panoply of species is adapted only to the current climatic regime, and changing that regime means certain death, i.e. extinction.

That’s an easy, simplistic sell, but it denies some of the subtleties of organismal biology. Four decades ago, scientists realized that evolution has preserved a variety of responses to environmental change. It turns out that our enzymes, the basic material that catalyze life as we know it, actually change their shape as climate changes. Whether this is because we have so much information stored in our DNA that has survived countless generations and a variety of climates, or whether the response is simply built into the enzymes is unknown, but it is ubiquitous. It even has a catchy name: “Phenotypic Plasticity.”

Before your eyes glaze over, a little explanation is in order.

Each one of us has a genotype, which is our DNA, and each of us has an expression of that, our “phenotype.” Obviously not all genes express themselves—if they did, our physiological destiny would be eminently predictable, but it is not. Instead, we all carry strands of DNA that could theoretically cause major disease that generally do not express (or “penetrate” in the lingo of biology), and we also have DNA that could probably defeat many of the aging processes, that similarly do not express.

Instead, organisms display “plastic” responses when their environment changes. And so, species-related concerns over potential CO2-induced global warming may be dramatically overblown. And, though they don’t get much publicity, scientists are continually documenting our amazing adaptability.