4 Steps to Evolution introduces a 4 step process to the formation of our Solar System and all life in it:
- Step 1: The birth of a Solar System & ALMA images show how our Solar System formed out of a Supernova, and how our Earth formed with all of the ‘material’ for life – the micro-organisms, gases and chemicals.
- Step 2: Friction at the Core describes how life began and is sustained on Earth by heat and energy provided by the Earth’s Core. Magnetism – Earth’s Guiding Force? describes how magnetism created by the Core permeates and guides life on Earth.
Step 3: Punctuated Equilibria and Step 4: The Sacred Path of Migration describe how evolution works. Quoting Earth Mother Our Womb of Life:
Present day ideas about evolution arise from those of Charles Darwin, who envisioned many, small transitional changes in organisms, with off spring varying slightly from their parents. As a small change proved advantageous, it was implemented. As later changes brought further improvements for survival and reproduction, they were carried into future generations. However, all efforts to trace the origin of man are dependent upon a fossil record which is unable to provide an unbroken series of transitional forms. Rather than supporting an unbroken pattern of development, fossil evidence strengthens the case for punctuated equilibria.
Our fossil record doesn’t match our explanation for evolution. The quote below from the textbook: “Explore Evolution” explains how “punctuated equilibria” (or equilibrium) came about:
“Many paleontologists are well aware of the conflict between the fossil record and neo-Darwinian theory [Darwin’s theory is now known as ne0-Darwinism since the inclusion of genetics]. In the traditional view, the fossil record was always to blame for the missing pieces of the evolutionary puzzle. Darwin, himself, had said the fossil record was ” woefully incomplete”.
By the early 1970s, some scientists including paleontologists Niles Eldredge and the late Stephen Jay Gould, began to become dissatisfied with this explanation. “We paleontologists,” wrote Eldredge, “have said that the history of life supports that interpretation [of gradual adaptive change], all the while really knowing that it does not.”
Eldredge and Gould decided to take a different approach. Instead of blaming the fossil record, they accepted the fossil data at face value. They agreed that the fossil record really does show many groups of organisms appearing abruptly, continuing for millions of years and then going extinct. “Stasis is data,” they insisted. Eldredge and Gould advocated a new evolutionary theory, called “punctuated equilibrium”.”
“Punctuated equilibria” means that evolution takes place in a series of sudden and repeated changes. According to punctuated equilibria, our solar system is the scene of regular changes, where long periods of equilibrium (relative uniformity) are interrupted by brief periods of excitation (punctuation). This throws a very different light on evolution.
“Punctuated Equilibrium was immediately attractive to many paleontologists because it described the fossil record more accurately than neo-Darwinism had done. However, many critics of the theory pointed out that punctuated equilibrium has never explained how the major changes recorded in the fossil record could have taken place in such a short time.”
The last sentence is important – although punctuated equilibria (or equilibrium) matched the fossil record, it proved problematic because:
- paleontologists could not provide an explanation for the punctuations; and
- how could life evolve so dramatically and so quickly after the punctuations?
This post answers the first problem: What event occurred on Earth to cause global extinction?
My next post will answer the second problem: How did life evolve so dramatically and quickly after the punctuations?
First I want to look at two of the most interesting and dramatic ‘punctuations’ in our fossil record:
The first is the Cambrian Explosion which is when, as the name suggests, complex life forms burst onto the scene. Before the Cambrian Explosion, the Earth was covered in single-cell organisms – bacteria. Then a global event occurred and life changed into multi-cellular structures – many with eyes, limbs, dorsal nerve chords and hard bodies – in fact, all of the 26 body types that now exist on Earth started during the Cambrian Explosion.
The second ‘punctuation’ is when dinosaurs became mammals.
Both of these punctuations were dramatic and rapid. Both of these punctuations share something in common: a thin layer of rock between the ‘before’ and ‘after’ fossils. And that thin layer of rock contains an abundance of a particular chemical that is very rare on the surface of Earth – iridium. Quoting Wikipedia:
“Iridium is the second-densest element (after osmium) and is the most corrosion-resistant metal, even at temperatures as high as 2000 °C… It is thought that the total amount of iridium in the planet Earth is much higher than that observed in crustal rocks, but as with other platinum group metals, the high density and tendency of iridium to bond with iron caused most iridium to descend below the crust when the planet was young and still molten.”
Iridium is not only found in abundance deep within the belly of the Earth, but also in meteors. So why is this important in the study of evolution?
The importance of the iridium-rich layers (known as iridium anomalies) in explaining evolution was first noted by a research team at UC Berkeley campus in the 1970s, headed by physicist Luis Alvarez. There is a wonderful article published in 1979, by the Lawrence Berkeley Laboratory (LBL), entitled “Berkeley Scientists Report First Evidence That Dinosaur Extinction Caused By Meteorite Impact” which describes how Alvarez and his team arrived at the theory that a giant meteor hit the Earth and caused the mass extinction of the dinosaurs. Their theory (published in 1980) is now the standard explanation for the extinction of the dinosaurs – but few people understand on what they based their proposal. Quoting from the article:
“If there was an increase in the deposition rate of iridium-rich material, a source on the earth would be unlikely, since iridium is one of the least abundant elements in the earth’s crust,” comments Asaro. “If, on the other hand, the source is extraterrestrial, it would be naturally enriched in iridium and would be compatible with our measurements. So we believe the extraterrestrial hypothesis is more likely.”
In other words, they claim the high levels of iridium found in the K-T boundary came from a meteor because: “a source on the earth would be unlikely”. A source from Earth is not ruled out by evidence, but rather, they couldn’t think of how the Earth could be the source.
In support of Alvarez’s theory a large crater was found off the east coast of Mexico, known as the Chicxulub crater, and it was deemed to be the crash site. But there are problems with this site – scientists have found that the crater pre-dates the extinction of the dinosaurs – fossils that shouldn’t be there have been found above the crater.
“Research, led by Gerta Keller of Princeton University in New Jersey, and Thierry Adatte of the University of Lausanne, Switzerland, uses evidence from Mexico to suggest that the Chicxulub impact predates the K-T boundary by as much as 300,000 years… “We found that not a single species went extinct as a result of the Chicxulub impact,” says Keller. ~ New Blow Against Dinosaur-killing Asteroid Theory, Geologists Find, Science Daily
Other scientists question the validity of using iridium as evidence of a meteor impact:
“Recent theoretical studies (Vickery and Melosh, 1990) suggest that large impacts may produce relatively weak iridium anomalies, because most of the vaporized impactor is blown off the Earth in the energetic collision.” ~ Future Climates of the World: A Modelling Perspective (1995)
An inherent problem with Alvarez’s asteroid impact theory is that it always remains theoretical – a best guess scenario – like trying to figure out a car crash from long ago when there are no witnesses and the crash site has degenerated over time.
Yet the asteroid impact theory remains ensconced in evolutionary science. As long as the source of iridium from Earth is denied, then we are left with little or no choice other than meteoric impact.
It is easy to claim ‘a truth’ when there is no alternative on offer.
Earlier I mentioned the Cambrian Explosion. It links to the punctuation between dinosaur and mammal through iridium. In the abstract of a scientific article entitled: “Explosive bolide impact designates the Cambrian Explosion, terminating the Cambrian event in New York” the author Gerald Friedman describes a conference he chaired in 1980, in which Louis Alverez and his son first announced that an asteroid 10km wide struck the Earth, causing a series of global catastrophes which killed the dinosaurs. Friedman was blown away by Alverez’s claim and checked for iridium in his Cambrian fossils samples in NY, his neck of the global evolutionary woods. Friedman too found iridium. He wrote:
“From these iridium anomalies I concluded that an extraterrestrial source, namely an asteroid, produced the iridium anomalies in the Cambrian of New York.”
If we look past Friedman’s conclusion – his interpretation of the data, and simply look at the data, then we find striking similarities between both evolutionary jumps in our fossil record – something happened which left a marker of iridium, that resulted in life transforming into greater complexity and diversity. Not only animal life but plants and the environment. Whatever the event was – it changed the very body of the Earth at a global level.
And it was not the only time this happened. The BBC webpage on pre-historic Earth gives a very good illustration of the different stages in Earth’s development – each stage marked by a global extinction/transformation event.
We tend to look at these stages as ‘mass extinction events’, but that is only half (or less) of the story – like saying the cocoon marks the mass extinction of caterpillars. It is true in one sense, but it completely negates the other side of the story – that the cocoon is a necessary step in the transformation of caterpillar to butterfly. Perhaps a better way to look at the punctuations are ‘periods of excitation’.
The mechanism the Punctuates our Equilibrium
Thank you for reading this far! Now that I’ve provided the background I will explain Step 3. As I described in an earlier post the Core of a planet forms through process of planetary differentiation. Differentiation is a process of separation that happens over time – heavier materials sink towards the core of a planet and lighter materials rise. This is how the heavy metal Core forms in the centre of a planet. The video below from the University of Nebraska describes the process.
As shown in the video, differentiation can take time – but it is also a continual process which only stops when the materials are properly separated. And this is the key! The Core of a planet keeps growing and eventually it outgrows its home – eventually the Core becomes too large and heavy for the planet to contain and it is ejected.
The ejection of the Core explains the sudden extinction of life – the punctuations in our fossil record. And it also explains the presence of iridium as a marker in the fossil record. Iridium exists in great quantity in the belly of the Earth – the Core’s birth would bring it to the surface and into the atmosphere to be spread around the Earth.
The image below includes 2 photos that are meant to illustrate a giant meteor hitting the Earth and causing the mass extinction of life. But perhaps a better way to view them is as the ejection or birth of a Core – a ‘period of excitation’ – the catalyst for the evolution of life.
Once a Core is ejected it settles close to the body of a planet as a satellite – a moon. I examine the evidence in great depth in the post: A Core Becomes a Moon.
The majority of this post focused on iridium as a marker of the punctuations in our fossil record, but there is actually a more common marker – volcanic ash and lava. As Gerta Keller pointed out in her case against meteoric impact in the extinction of the dinosaurs:
“None of the other great mass extinctions are associated with an impact, and no other large craters are known to have caused a significant extinction event.”
Keller suggests that the massive volcanic eruptions at the Deccan Traps in India may be responsible for the extinction, releasing huge amounts of dust and gases that could have blocked out sunlight and brought about a significant greenhouse effect.” ~ New Blow Against Dinosaur-killing Asteroid Theory
Volcanic eruptions are linked time and time again to the extinction events in our fossil record. And this is exactly what we would expect if a Core were ejected – because the Core is nestled in the heart of the Earth in an ocean of magma (1400 miles thick at last count), so its ejection would bring the magma to the surface. As noted in an article from Columbia University (see below) which looked at the extinction of the pre-dinosaurs – the link between the mechanism of extinction and volcanism “is pretty much ironclad”:
“Scientists examining evidence across the world from New Jersey to North Africa say they have linked the abrupt disappearance of half of earth’s species 200 million years ago to a precisely dated set of gigantic volcanic eruptions… “This may not quench all the questions about the exact mechanism of the extinction itself. However, the coincidence in time with the volcanism is pretty much ironclad,” said coauthor Paul Olsen, a geologist at Columbia University’s Lamont-Doherty Earth Observatory who has been investigating the boundary since the 1970s.” ~Mega volcanoes Tied to Pre-Dinosaur Mass Extinction