INTELLIGENT DESIGN ???

Collisions of Stars

Background

Like human beings, stars evolve and change their appearance substantially during their lifetime. They are born from the collapse of huge galactic gas clouds and contract under the influence of gravity until they become hot enough for nuclear reactions to ignite their interior. Stars spend most of their life burning their nuclear fuel quietly. A good example of a typical star, a so-called Main Sequence Star, is our sun that is currently burning hydrogen into helium. Once their nuclear fuel is exhausted, stars die. Depending on their mass they either blow up tremendously first, then eject their envelopes and finally leave behind a cold and very dense remnant, a so-called White Dwarf, or they end their lives in a spectacular explosion, a Supernova. Such a Supernova leaves behind the most exotic objects in the universe: either a Neutron Star, something like a giant atomic nucleus of about 10 km radius, or a Black Hole.

Collisions between stellar objects do occur quite frequently in the universe, either in places with a high density of stars like in a Globular Cluster  or in binary systems, that emit according to Einstein's Theory of General Relativity Gravitational Waves and finally coalesce. Collisions between a Black Hole of a few solar masses and stars like our sun occur quite frequently in Globular Clusters.

The Five Worst Extinctions in Earth's History

Here are details of the five worst mass extinctions in Earths history and their possible causes, according to paleobiologist Doug Erwin of the Smithsonian Institutions National Museum of Natural History. Erwin said estimates of extinction rates are from the late John J. Sepkoski at the University of Chicago:

Cretaceous-Tertiary extinction, about 65 million years ago, probably caused or aggravated by impact of several-mile-wide asteroid that created the Chicxulub crater now hidden on the Yucatan Peninsula and beneath the Gulf of Mexico. Some argue for other causes, including gradual climate change or flood-like volcanic eruptions of basalt lava from Indias Deccan Traps. The extinction killed 16 percent of marine families, 47 percent of marine genera (the classification above species) and 18 percent of land vertebrate families, including the dinosaurs.

End Triassic extinction, roughly 199 million to 214 million years ago, most likely caused by massive floods of lava erupting from the central Atlantic magmatic province -- an event that triggered the opening of the Atlantic Ocean. The volcanism may have led to deadly global warming. Rocks from the eruptions now are found in the eastern United States, eastern Brazil, North Africa and Spain. The death toll: 22 percent of marine families, 52 percent of marine genera. Vertebrate deaths are unclear.

Permian-Triassic extinction, about 251 million years ago. Many scientists suspect a comet or asteroid impact, although direct evidence has not been found. Others believe the cause was flood volcanism from the Siberian Traps and related loss of oxygen in the seas. Still others believe the impact triggered the volcanism and also may have done so during the Cretaceous-Tertiary extinction. The Permian-Triassic catastrophe was Earths worst mass extinction, killing 95 percent of all species, 53 percent of marine families, 84 percent of marine genera and an estimated 70 percent of land species such as plants, insects and vertebrate animals.

Late Devonian extinction, about 364 million years ago, cause unknown. It killed 22 percent of marine families and 57 percent of marine genera. Erwin said little is known about land organisms at the time.

Ordovician-Silurian extinction, about 439 million years ago, caused by a drop in sea levels as glaciers formed, then by rising sea levels as glaciers melted. The toll: 25 percent of marine families and 60 percent of marine genera.

Throughout the history of life, extinction has been a natural and inherent part of the Earth's ever-fluctuating biodiversity.  Environmental changes and interspecific competition necessarily produce "unsuccessful" organisms, species not well suited for survival in their ecological niche.  The result of such a condition is either evolutionary adaptation or extinction.  In the latter case, an evolutionary line is ended, and, as is often the case, new lines emerge to fill the vacated niche space.  Thus, life forms appear and disappear and biodiversity is maintained through a complex balance of speciation and extinction.

The only explanation that has been posed, and, perhaps, the only explanation that can be posed for periodicity is that mass extinctions have and ultimately extraterrestrial cause.  Astronomical forces seem to be the only ones to act with sufficient precision to explain the rather exact schedule of mass extinction events under the periodic theory.  The regular timing of the cosmos could possibly inflict mass extinction on the Earth via climatic changes or even regular bolide impact events.  In the case of the latter, it has been postulated that periodic disturbances in the comet cloud, perhaps caused by the passage of our solar system through the outer reaches of the Milky Way or by a hypothetical dark star or tenth planet, send comets hurtling toward Earth at regular intervals.



Mass extinctions are often signifiers of large-scale climatic, environmental changes, often global in nature.  Many organisms are naturally unfit for these changes and are lost, while some adapt to the changed environment.  Mass extinctions often leave behind a great deal of unused niche space and the opportunity for adaptive radiation is great.  Trends will of course appear as the fossil record is viewed over the long term.  Some taxa will survive well through the traumatic mass extinction events while other forms will be repeatedly lost.  Specific examples will be examined later in respect to each major extinction event.  One of the most important aspects of the macroevolutionary record is the profound differences found between what adaptations are helpful in regard to "everyday" survival and survival in the midst of a mass extinction event.  In this way, these events significantly shape what lines persist and what lines become evolutionary dead ends.

References
Donovan, Stephen K. Mass Extinctions.  New York: Columbia University Press, 1989.
Ridley, Marc. Evolution.  Cambridge, Massachusetts: Blackwell Science, 1996.
Stanley, Steven M. Extinction.  New York: Scientific American Books, 1987.

     Now does any of the foregoing support belief in an almighty, omnipotent, omniscient, omni benevolent deity who created everything directly and for a specific purpose and who “numbers the hairs on our heads and notices even the fall of a sparrow”? Of course fundamentalists would argue that the reason for planetary calamities and imperfections in animal and human life forms is all due to Original Sin. However I don’t believe that Adam and Eve existed when all of the aforementioned global calamities and extinctions of life took place some 65 million plus years ago.