Category Archives: Technology & Gear

How Cyclical Volcanic Activity Benefits Humanity

When we think about volcanoes, the images that typically come to mind are violent eruptions that devastate the surrounding landscapes and bring death or serious injury to anyone so unfortunate as to be in the vicinity. Figure 1, for example, shows the lava flows from the 1985 eruption of the Nevado del Ruiz volcano, which killed more than 23,000 people and destroyed the town of Armero, Colombia.

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Figure 1: Town of Armero, Colombia, wiped out by the 1985 eruption of Nevada del Ruiz

People are quick, however, to return to the regions near recent volcanic eruptions. The reason why is that the volcanic rocks and ash from eruptions contain stores of rich nutrients that yield bumper harvests of food crops.

This curse and blessing of volcanic eruptions raises an interesting question: wouldn’t it be great if volcanic eruptions were especially frequent when nobody lived near the volcanoes and especially infrequent when people were exploiting their rich soils for food? A recently published paper by five geologists shows that such a marvelous timing has indeed occurred, and it ranks as yet another fine-tuned feature of our planet that allows humans to enjoy sustained global high-technology civilization.

The paper published in Quaternary Science Reviews updates a hypothesis, based on evidence that volcanic activity in Iceland increased after the last glacial maximum, that deglaciation produces enhanced volcanic activity.1 The five geologists reanalyzed the four longest and most reliable tephra records.

Tephra is fragmented material ejected by a volcanic eruption regardless of fragment size, composition, or how the fragmented material got to its location. Where the tephra is hot enough, it will fuse together into pyroclastic rock or tuff (volcanic ash compacted to form solid rock). Figure 2 shows tephra layers from multiple eruptions of the Hekla volcano.

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Figure 2: Tephra Layers in South Central Iceland from the Hekla Volcano

The geological team investigated four tephra records that covered multiple glacial cycles. These four records were all linked with oxygen-18 measurements that accurately revealed both the recent historical records of sea level variations and variations in the global mean (average) temperature. Scientists obtained the four tephra records from different latitudes and different geotectonic settings.

All the tephra records exhibited the Milankovitch periodicities of precession (23,000 years), rotation axis tilt (41,000 years), and orbital eccentricity (approximately 100,000 years). I have written previously about Earth’s Milankovitch cycles here,2 here,3 and here,4 and how they in large part explain the repeated episodes of glaciations and deglaciations that characterize the ice age cycle of the past 2.588 million years.

All the tephra records show that periods of increased volcanic eruption frequencies coincide with the dramatic deglaciations that occur at the glacial-interglacial transitions. Evidently, the release of the load of ice and snow on the continental landmasses ignites volcanic eruptions.

The long duration tephra records in this study, however, add up to just four. Thus, the five geologists call for “more precise tephra time series (preservation and age optimized) from different regions (glaciated versus non-glaciated) and geological settings (island arcs, continental arcs, intraplate)”5 … “to decipher the impact of these factors on a global perspective of how climate may control volcanism.”6

Enhanced volcanic eruptions at the beginning of an interglacial period imply that much of Earth’s continental landmasses and its lakes, rivers, and oceans receive a delivery of nutrients that allows microbes, vegetation, and animals to flourish. This fertilization event coincides with another fertilization event that I wrote about in Improbable Planet. I stated there that at the beginning of an interglacial “fine loess (wind-blown dust) from dried-out parts of the floodplains of glacial braided rivers carried layers of crucial nutrients onto the lowland plains below, making them richly fertile.”7

As I have explained in another blog,8 the interglacial we are experiencing right now is unique. It is the longest lasting interglacial and the only one where there has been an extended duration (9,500 years) of extreme climate stability. The current warm period has followed the most severe glacial period in the entire ice age cycle.

The severity and rapidity of the deglaciation from that glacial period resulted—at the time of the beginning of our interglacial period—in the greatest delivery of fine loess and other nutrients from volcanic eruptions. These especially intense and simultaneous fertilization events, to a large degree, explain why humans today are able to grow so much food on Earth’s plains and valleys and why we are able to harvest so much shellfish and other fish from Earth’s oceans, seas, lakes, and rivers.

These especially intense and simultaneous fertilization events give us more reasons to thank God for his supernatural blessings poured out on humanity. They also demonstrate that God planned in advance that billions of us would experience sufficiently high-technology civilization that makes possible the rapid spread of his message of redemption from human sin.

Original article: How Cyclical Volcanic Activity Benefits Humanity

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Long Noncoding RNAs Extend the Case for Creation

I don’t like to think of myself as technology-challenged, but I am beginning to wonder if I just might be. As a case in point, I have no clue about all the things my iPhone can do. It isn’t uncommon for someone (usually much younger than me) to point out features of my iPhone that I didn’t even know existed. (And, of course, there is the TV remote—but that will have to serve as material for another lead.)

The human genome is a lot like my iPhone. The more the scientific community learns about it, the more complex it becomes and the more functionality it displays—functionality about which no one in the scientific community had a clue. It has become commonplace for scientists to discover that features of the human genome—long thought to be useless vestiges of an evolutionary history—actually serve a critical role in the structure and function of the genome.

Long noncoding RNAs (lncRNAs) illustrate this point nicely. This broad category of RNA molecules consists of transcripts (where genetic information is transferred from DNA to messenger RNA) that are over 200 nucleotides in length but are not translated into proteins.

Though numbers vary from source to source, estimates indicate that somewhere between 60 to 90 percent of the human genome is transcribed. Yet only 2 percent of the genome consists of transcripts that are directly used to produce proteins. Of the transcripts that are untranslated, researchers estimate that somewhere between 60,000 to 120,000 of the transcripts are noncoding RNAs. Researchers categorize these transcripts as microRNAs(miRNAs), piwi-interacting RNAs (piwiRNAs), small interfering RNAs (siRNAs) and lncRNAs. The first three types of RNAs are relatively small in size and play a role in regulating gene expression.

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Figure 1: Transcription and Translation

Initially, researchers thought for the most part that lncRNAs were transcriptional noise—junk. But this view has changed in recent years. Evidence continues to accrue demonstrating that lncRNAs play a wide range of roles in the cell.1 And as evidence for the utility of lncRNAs mounts, the case for the design of the human genome expands.

The Functional Utility of Long Noncoding RNAs

As it turns out, lncRNAs are extremely versatile molecules that can interact with: (1) other RNA molecules, (2) DNA, (3) proteins, and (4) cell membranes. This versatility opens up the possibility that these molecules play a diverse role in cellular metabolism.

Recently, Harry Krause, a molecular geneticist from the University of Toronto, published two review articles summarizing the latest insights into lncRNA function. These insights, including the four to follow, demonstrate the functional pervasiveness of the transcripts.

lncRNAs regulate gene expression. lncRNAs influence gene expression by a variety of mechanisms. One is through interactions with other transcripts forming RNA-RNA duplexes that typically interfere with translation of protein-coding messenger RNAs.

Researchers have recently learned that lncRNAs can also influence gene expression by interacting with DNA. These interactions result in either: (1) a triple helix, made up of two DNA strands intertwined with one RNA strand, or (2) a double helix with the lncRNA intertwined with one of the DNA strands, leaving the other exposed as a single strand. When these duplexes form, the lncRNA forms a hairpin loop that can either indiscriminately or selectively attract transcription factors.

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Figure 2: A Hairpin Loop

Though researchers are still learning about the role lncRNAs play in gene regulation, these varied interactions with DNA and proteins suggest that lncRNAs may influence gene expression through a variety of mechanisms.

lncRNAs form microbodies within the nucleus and cytoplasm. A second function recognizes that lncRNAs interact with proteins to form hydrogel-like structures in the nucleus and cytoplasm. These structures are dense and heavily cross-linked subcellular structures that serve as functionally specific regions without a surrounding membrane. (In a sense, the microbodies could be viewed as somewhat analogous to ribosomes, the protein-RNA complexes that synthesize proteins.) In the nucleus, microbodies play a role in transcriptional processing, storage, and stress response. In the cytoplasm, microbodies play a role in storage, processing, and trafficking.

lncRNAs interact with cell membranes. A third role stems from laboratory studies where lncRNAs have been shown to interact with model cell membranes. Such interactions suggest that lncRNAs may play a role in mediating biochemical processes that take place at cell membranes. Toward this end, researchers have recently observed certain lncRNA species interacting with phosphatidylinositol 3,4,5-triphosphate. This cell membrane component plays a central role in signal transduction inside cells.

lncRNAs are associated with exosomes. Finally, lncRNAs have been found inside membrane-bound vesicles that are secreted by cells (called exosomes). These vesicles mediate cell-cell communication.

In short, the eyes of the scientific community have been opened. And they now see the functional importance and functional diversity of lncRNAs. Given the trend line, it seems reasonable to think that the functional range of lncRNAs will only expand as researchers continue to study the human genome (and genomes of other organisms).

The growing recognition of the functional versatility of lncRNAs aligns with studies demonstrating that other regions of the genome—long thought to be nonfunctional—do, in fact, play key roles in gene expression and other facets of cellular metabolism. Most significantly, toward this end, the functional versatility of lncRNAs supports the conclusions of the ENCODE Project—conclusions that have been challenged by some people in the scientific community.

The ENCODE Project

A program carried out by a consortium of scientists with the goal of identifying the functional DNA sequence elements in the human genome, the ENCODE Project, reported phase II results in the fall of 2012. (Currently, ENCODE is in phase IV.) To the surprise of many, the ENCODE Project reported that around 80 percent of the human genome displays biochemical activity—hence, function—with the expectation that this percentage should increase as results from phases III and IV of the project are reported.

The ENCODE results have generated quite a bit of controversy. One of the most prominent complaints about the ENCODE conclusions relates to the way the consortium determined biochemical function. Critics argue that ENCODE scientists conflated biochemical activity with function. As a case in point, the critics argue that most of the transcripts produced by the human genome (which include lncRNAs) must be biochemical noise. This challenge flows out of predictions of the evolutionary paradigm. Yet, it is clear that the transcripts produced by the human genome are functional, as numerous studies on the functional significance of lncRNAs attest. In other words, the biochemical activity detected by ENCODE equates to biochemical function—at least with respect to transcription.

A New View of Genomes

These types of insights are radically changing scientists’ view of the human genome. Rather than a wasteland of junk DNA sequences stemming from the vestiges of an evolutionary history, genomes appear to be incredibly complex, sophisticated biochemical systems, with most of the genome serving useful and necessary functions.

We have come a long way from the early days of the human genome project. When completed in 2003, many scientists at that time estimated that around 95 percent of the human genome consists of junk DNA. That acknowledgment seemingly provided compelling evidence that humans must be the product of an evolutionary history.

Nearly 15 years later the evidence suggests that the more we learn about the structure and function of genomes, the more elegant and sophisticated they appear to be. It is quite possible that most of the human genome is functional.

For creationists and intelligent design proponents, this changing view of the human genome—similar to discovering exciting new features of an iPhone—provides reasons to think that it is the handiwork of our Creator. A skeptic might ask, Why would a Creator make genomes littered with so much junk? But if a vast proportion of genomes consists of functional sequences, this challenge no longer carries weight and it becomes more and more reasonable to interpret genomes from within a creation model/intelligent design framework.

Original article: Long Noncoding RNAs Extend the Case for Creation

Marine Engineering Saves Griend Island

Griend isle

Between Harlingen and Terschelling in the northern Netherlands, the hook-shaped island of Griend is an extremely valuable nature reserve, but it has been increasingly affected by erosion.

Boskalis project manager Johan Miedema said, “The Wadden Sea area is a UNESCO World Heritage site, and it is one of the most beautiful nature reserves in the Netherlands. But it is also a treacherous environment because the mud flats are submerged by the tide twice a day.

“Measures to save and stabilise Griend focused on building a foreshore,” he noted, “but the work had to be done quickly while keeping the disruption of nature to a minimum.

“We had to find creative solutions, and those included housing all our colleagues on dry land rather than in an accommodation vessel. In turn, it meant taking them to work in small boats and disembarking on a car connected to a bulldozer. But even then, they sometimes had to walk to work up to 2 km across the mud flats.”

Scope of Work

To save the island, Boskalis held consultations with the Dutch Directorate General for Public Works and Water Management (Rijkswaterstaat) and with the Dutch Society for the Preservation of Nature (Natuurmonumenten). As a result, a foreshore consisting of 250,000 m³ of sand on the southwestern part of the island was decided on.

This plateau, which covers about 18 ha, is semicircular and some of the sand used to build it was obtained by removing the top layer of a row of dunes on the north side of the island.

The remaining sand was excavated by cutter suction dredger Seine from the Blauwe Slenk area, the storage location for sand mined during maintenance dredging of the Wadden Sea shipping channels. It was then pumped through a 4.5 km pipeline with both floating and submerged sections.

As Miedema pointed out, building such a long pipeline is not the most obvious solution for a short-term project like this. But it was one of the creative solutions the company needed to find.

“We adopted this approach because it is far less disruptive than bringing in sand using trailing suction hopper dredgers,” he explained. “It was a complex logistical operation: we had to pass through small locks and shallow channels to get all the pipeline sections into place.

“We also had to keep an eye on high and low tides at all times,” he added. “That made positioning of the submerged pipeline a challenge, too. Time wasn’t on our side either. We had to work flat out day and night to get the job done before the start of the storm season.”

Mini Sand Motor

Excavators, shovels, bulldozers, and cranes were used to construct the foreshore, then shellfish banks 100 m long and 50 cm high were created at eight sites.

“It is expected that the combination of shells and sand from the top layer will be a good place for sea grass to grow and make the plateau stronger,” Miedema said.

“We have also made a 50 m-wide opening on the northern side of the island that allows the sea to flow in more often and to deposit more silt in the large salt marsh on the southern side. That silt will settle and harden in the years to come, providing the island with more robust coastal protection.

“The sand that is pumped in will spread along the coast of the island over time, like a small sand motor [similar in concept to the 1 km² sand motor created off South Holland to continually nourish the Delfland Coast].

“We expect this saltmarsh to eventually form the western edge of the island. The idea is that Griend will move about 7 m a year in a southeasterly direction, just like it used to.”

“Natuurmonumenten awarded us this project mainly because of all the measures we proposed to minimise any disruption of nature,” Miedema concluded. “For example, as well as walking to work, we also replaced the reversing alarms on our machines with air blowers and used green lights.

“All in all, it was quite a puzzle to get the job done quickly and properly. But that makes the result all the more satisfying.”

A Natura 2000 Site

Located about 12 km southwest of the island of Terschelling, to which it belongs in administrative terms, Griend is a Natura 2000 site and thus part of the European Union network of core breeding and resting areas for rare and threatened species – as well as some rare natural habitat types – stretching across all 28 countries.

Listed under both the Birds and Habitats directives, Natura 2000’s aim is to ensure the long-term survival of Europe’s most valuable and threatened species and habitats.

Griend used to be a lot larger and was inhabited for many years. Today, it is no longer open to the public to prevent any disturbance of the bird colonies.

The island hosts the largest tern colony in western Europe: more than 10,000 pairs breed there annually. It is also a breeding place for 50,000 birds, including common terns, oystercatchers, redshanks, and numerous ducks and gulls. Additionally, thousands of migratory birds stop at the island on their journey from Siberia to Africa, and it is a resting place for grey seals.

Original article: Griend Island

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