Study Explores Why Some Individuals Sacrifice To Help Others Reproduce, ScienceDaily, March 9, 2006. In a new study forthcoming in the April 2006 issue of The American Naturalist, Peter Nonacs [et al.] explore a theory of social behavior that seeks to explain why some individuals willingly sacrifice their own reproduction to help raise others' offspring. "Transactional Skew" (TS) theory proposes that such cooperation is possible through "shared reproduction," making it worthwhile to help close relatives because some of the same genes are getting passed along. Thus, the degree of shared reproduction should vary across groups by the degree to which they are related. However, in a study across four species of paper wasps
-- long considered one of the best examples supporting this theory -- the researchers found that not only was there cooperation and shared reproduction between sisters but also between distantly related or unrelated wasps. "This result strongly rejects the unique TS prediction that the level of cooperation should vary across groups according to the attributes of individual group members," says Nonacs. "[We] propose an alternative explanation in which wasps seek to cooperate with close kin, but less related groups sometimes form due to recognition errors." ... [So even in "one of the best examples supporting this theory," the Darwinist `selfish genes' explanation fails. If "wasps seek to cooperate with ...less related groups ...due to recognition errors" then those so-called "recognition errors" are the norm and that undermines the entire Darwinist `selfish genes' theory explanation of "why some individuals willingly sacrifice their own reproduction to help raise others' offspring"!]
Destroying Astrobiology Would be a `Disaster', SPACE.com, Rocco Mancinelli, SETI Institute, 4 March 2006 ...Astrobiology is the study of the origin, evolution, distribution, and future of life in the universe. As part of that, it seeks to understand the origin of the building blocks of life, how these building blocks combine to create life, how life affects and is affected by the environment from which it arose, and finally, whether and how life expands beyond its planet of origin. It requires studying fundamental concepts of life and habitable environments that will help us to recognize biospheres that might be quite different from our own. This includes studying the limits of life, life's phylogeny and effects of the space environment on living systems. Such fundamental questions require long term stable funding for the science community. This means keeping the NASA Astrobiology Institute (NAI) and the grants programs funded at healthy levels. The search for potentially inhabited planets beyond our solar system includes laboratory and field investigations of the origins and early evolution of life, and studies of the potential of life to adapt to future challenges, both on earth and in space. As such, astrobiology has never been, nor should it ever be, uniquely tied to a Mars Sample return mission, or human exploration of Mars. The broad interdisciplinary character of astrobiology compels us to strive for the most comprehensive and inclusive understanding of biological, planetary, and cosmic phenomena. NASA essentially developed astrobiology as a whole new interdisciplinary scientific field from scratch. It now has thousands of researchers, many international affiliates, multiple peer reviewed journals and is growing. Even NSF has been amazed by what NASA's astrobiology program has accomplished. Abandoning this field now would undermine some of the most exciting science NASA has going. ... [The fact is that astrobiology (i.e. exobiology renamed to make it sound like a new science), despite the billions spent on it, still "has yet to demonstrate that its subject matter exists", as Simpson pointed out over 40 years ago in 1964. The "thousands of researchers, many international affiliates, multiple peer reviewed journals and ... growing" is a byproduct of what origin of life researcher Jeffrey Bada noted of astrobiology that "one of the field's attractions was money--and lots of it." Indeed, such a large group of researchers dependent on ever-increasing amounts of taxpayer funding with no hard evidence "its subject matter exists," is a recipe to generate hyped claims about the existence of extraterrestrial life on various planets and moons (e.g. Saturn Moon Has Geysers, Hinting Life Is a Possibility, New York Times, March 10, 2006) both within and outside our Solar System. But personally I hope astrobiology does continue because its continual failure is evidence that life is unique to Earth!]
The Growing Habitable Zone: Locations for Life Abound, SPACE.com, Ker Than, 7 February 2006 ... In a galaxy filled with billions of stars, scientists searching for alien life need some way to pick out those which are most likely to harbor habitable planets and moons. For more than 150 years, an important tool in this screening process has been the concept of a "circumstellar habitable zone." Traditionally, this zone has been defined as a narrow disk around a star where temperatures are moderate enough that water on the surface of a planet can exist in a liquid form. The idea is that where liquid water exists, life might arise. Beginning in the latter half of the 20th century, new information began to emerge that challenged the traditional view. Scientists on Earth began finding rugged organisms thriving in harsh conditions that were off-limits to most other creatures. Meanwhile, images beamed back by robotic probes in space revealed that other moons within our solar system were much more interesting geologically-and perhaps biologically-than our own. However, beginning a decade ago, planets discovered around other stars began to reveal a diversity of planetary systems that was beyond expectations. More recently, scientists have gone back and reexamined their ideas about the possibility of habitable planet forming around red dwarf stars. Despite being the most abundant stars in the galaxy, red dwarfs have traditionally been shunned by scientists as being too small and too dim to support life. Those prejudices are beginning to fade and the recent discovery of a small, rocky world in orbit around a red dwarf 28,000 light-years from our corner of the solar system has refueled speculations that these stars might harbor planets with life ... [This older item from my backlog is a good (bad?) example of how astrobiology hypes up the case for extraterrestrial life. As pointed out in my post of 22-Feb-06, this "small, rocky world in orbit around a red dwarf" was "Just over five times heavier than Earth" and even "planets only a few times heavier than Earth ... the extra gravity ... would crush these minerals into ... semi-conductors or metals" resulting in "enhanced heat flow from the planet's core to the surface, which means more volcanoes and more `planetquakes':
"Astronomers have detected more than 150 planets orbiting nearby stars, raising hopes of finding another Earth ... But there may be more to finding that `goldilocks' planet, just the right size and distance from its star to match Earth, warns one research team. Last month, an international team reported in Nature that it had detected the smallest extrasolar planet orbiting a normal star yet. Just over five times heavier than Earth, OGLE- 2005-BLG-390Lb, is 28,000 light years away. It orbits two-and-a-half times further away from its star than Earth does the sun, and enjoys chilly temperatures of -364 degrees because of the dimness of its star. A few earlier discoveries of similarly-sized `extra solar' planets had also occurred, but all those orbit very close to their stars. But the discoveries show that astronomers are closing in on a planet in the `habitable zone' where temperatures are neither too cold or too hot for life ... But it may not be so easy, suggests University of Minnesota physicist Renata Wentzcovitch and colleagues in the current Science magazine. For `Super Earth' planets only a few times heavier than Earth, the interior chemistry of the planet's core may have a big effect on whether future space tourists will ever want to vacation there. In the study, the team looked at the `Super Earth' orbiting the star Gliese 876, 15 light years away. The researchers analyzed the chemistry of perovskite, an electronically inert mineral made of oxygen, silicon and magnesium, found in the mantle covering the iron cores of planets. On Earth, there is a thin layer of the stuff in the mantle. Through computer simulations, the study team found the extra gravity of a `Super Earth' (twice as strong on its surface as Earth's) would crush these minerals into new forms, ones that would take on the properties of semi-conductors or metals ...The result there would be enhanced heat flow from the planet's core to the surface, which means more volcanoes and more `planetquakes.' The effects on the planet's magnetic field, which on Earth shields the surface from solar radiation, of increased electrical activity in the mantle are more difficult to figure out, she says. The larger point is there is more to finding another Earth than detecting a planet the same size and same distance from its star, she says. Venus and Earth are very similar, she notes, but have significant differences in their interior chemistry. Venus has a more viscous interior that lead to a planet-sized earthquake hundreds of millions of years ago, she says, and that likely also explains the hellish conditions there, where 800-degree winds are lashed by sulfuric acid rain." (Vergano D., "Finding 'Super Earth' is a 'Goldilocks' errand," USA Today, February 19, 2006)
So from the failure to find truly Earth-like planets in a "circumstellar habitable zone," i.e. "a narrow disk around a star where temperatures are moderate enough that water on the surface of a planet can exist in a liquid form," astrobiology is now trying to make a virtue out of necessity by appealing to "a diversity of planetary systems that was beyond expectations" and ... rugged organisms thriving in harsh conditions that were off-limits to most other creatures". But these "harsh conditions" on Earth are still moderate compared with those on other planets and exoplanets. And that some organisms can adapt to extreme conditions (by Earth's standards) does not mean they could originate in such conditions. Such extremophiles have very complex genetic repair systems:
"How do they do it? What defenses do these frequently diminutive creatures (many are microbial, although not all - think penguins) mount against environmental conditions that would either pickle or pyrolize you and me? There are two fundamental strategies: erect a barrier against the elements, or change your metabolism. For example, some halophiles protect themselves from a saline environment by increasing the concentration of salts in their innards. With salinity about the same both within and without the cell, the halophile needn't fear that runaway osmosis will drain it of its precious water. If you can't defend against a brutal habitat, you can learn to love it. For example, psychrophiles come equipped with special proteins to adapt their lifestyle to the cold. Some of these proteins act as antifreeze to lower the freezing point of water, to prevent its congealing, expanding, and sundering the cell. Other proteins (enzymes) are specially formulated to ensure that chemistry continues even when the temperature dips to the single digits or lower. Many researchers are looking for ways to exploit the Darwinian inventiveness that has produced these extremophile defense mechanisms. For example, Deinococcus radiodurans, which boasts a highly sophisticated DNA repair shop within its tiny cell walls, is able to recover from exposure to massive doses of molecule-busting, high energy radiation by simply fixing the damage. It's hoped that this talent will prove useful in engineering microbes that can clean up radioactive spills, or possibly even protect us from skin cancer." (Shostak S., "Extremophiles: Not So Extreme?," SPACE.com/SETI Institute, 4 August 2005)
which would be an even greater problem for evolution if the original living organism "boasts a highly sophisticated DNA repair shop within its tiny cell walls"! Mind you, as it is, even simplest living organism has "a highly sophisticated DNA repair shop within its tiny cell walls"! In fact this very morning in my first draft of my book, "Problems of Evolution," I added to chapter 11 Major Transitions, 11.1 "Non-living to prokaryote," sections 11.1.6 "Error-checking" and 11.1.7 "Self-repair" to the necessary capabilties that the earliest living organisms would need to have.]
Stephen E. Jones, BSc (Biol).
"Problems of Evolution"
"Now we will revert simply to the consideration of the theory of `Natural Selection' itself. ... If the theory of Natural Selection can be shown to be quite insufficient to explain any considerable number of important phenomena connected with the origin of species, that theory, as the explanation, must be considered as so far discredited. If other causes than Natural (including sexual) Selection can be proved to have acted-if variation can in any cases be proved to be subject to certain determinations in special directions by different means than Natural Selection, it then becomes antecedently probable that it is so in other cases, and that Natural Selection depends upon, and only supplements, such means; which conception is opposed to the pure Darwinian position." (Mivart S.J., "On the Genesis of Species," Macmillan & Co: London & New York , Second edition, 1871, pp.21-22. Emphasis original)
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