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MAVs and Fruit Flies: Unguided Evolution Smarter Than Top Scientists


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Autonomous air vehicles are finding increasing use and the Air Force is interested micro versions:

Micro Air Vehicles (MAVs) typically UAVs with wingspan on the order of 15cm or less are fast becoming commonplace for meeting a wide range of current and future military missions.

But there are tremendous technical challenges:

A typical sensor suite for a MAV consists of GPS, MEMs-based linear accelerometers, angular rate sensors, magnetometers, and barometric-altimeters. While this is adequate for waypoint navigation, the potential of MAVs to replicate the flight agility of natural fliers (e.g., birds, bats, insects) remains elusive, especially in complex terrain such as city streets or forests.

For hints at how to solve such problems designers are looking at nature’s solutions:

The desire to engineer the agility of natural fliers has led researchers to the study of flying organisms to learn how animals combine sensory input with control output to achieve flight maneuverability. Biologists are beginning to understand how visual information is integrated with mechanosensory information in biological systems for flight stabilization, landing, and prey/mate pursuit. Studies are also underway to discover how proprioceptive sensory feedback is used for fine-scale control the movement of wings, legs, etc. during aggressive maneuvers (e.g., obstacle or collision avoidance). These sensory modalities are combined with olfactory or auditory information for predator avoidance and prey/mate pursuit.

Fortunately evolution has created highly advanced flight systems:

The fact that animals such as fruit flies exhibit such remarkable flight agility with many sensory inputs and modest onboard processing suggests a particular kind of coupling between sensing, control and dynamics altogether qualitatively different from that of engineered systems. Advancements in flow control have made it possible to control the separation of flow around wings, either to inhibit separation for higher cruise lift-to-drag ratios or to promote it for large transients in aerodynamics loading for aggressive maneuvers. Natural flyers have anatomic features which probably act as flow control devices (e.g., covert flaps) and may act as aerodynamic sensors.

But understanding evolution’s marvels remains a research challenge:

Rigorous system modeling that can accurately capture the vehicle dynamics, sufficiently accounting for uncertainties in aerodynamic and structural models, remains primitive even for engineered vehicles, let alone for natural flyers. Uncertainty arises both in the veracity of particular models in describing a given flow or dynamics phenomenon, and in unknowns in the inputs, such as wind gusts and their time-dependent effect on the vehicle. While on-going research efforts are addressing some of the critical limitations in this area, significant uncertainties in the dynamics models of MAVs are unlikely to be completely eliminated.

How do random mutations produce such brilliant designs? Answering such questions is, of course, what science is all about. As Darwin explained, evolution opens up wide areas of scientific research. But now we know it also gives top scientists hints to their toughest problems.

Fossil Find: Fungus Controlled Ant Just Like Today


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The fossil record cannot usually tell us about the soft body parts or the behavior of its specimens. For these, we look to the extant species. But now a clever finding reveals an odd behavior in carpenter ants from the distant past.

Nature is full of designs and behaviors not easily preserved in the fossils. Consider the bat, certain types of which map out objects around it as small as a mosquito by sensing the echoes of its own squeaks—a system known as echolocation. The bat emits a high-pitch squeak, well beyond the range of human hearing, up to 2,000 times per second. Next it determines both range and direction to the tiny mosquito by sensing the echo while filtering out echoes from the squeaks of nearby bats. Or consider fish that use underwater electric fields either passively or actively to sense objects around them, including other fish.

It is difficult to determine such details from the fossil record, but they reveal how unlikely is the theory of evolution. Anyone familiar with today’s sonar or radar systems knows the immense complexity involved with such systems: the problems of sensing the echo in the presence of the transmitted signal which can be billions of times stronger, of filtering out spurious signals such as echoes of older transmissions, of combining the echo information with knowledge of your own motion, and so forth. Yet the bat’s detection abilities are superior to those of the best electronic sonar equipment.

It is also difficult to determine complex behaviors from the fossil record. Consider certain Hydra species, a small underwater creature, that develop nematocysts—stinging cells which eject a tiny poisoned hair. A planarian worm known as the Microstomum, consumes Hydra but passes the nematocysts through its digestive system and positions them on its surface. The Hydra meal serves to arm the Microstomum, and when fully equipped the Microstomum omits the Hydra from its diet, resuming again after discharging its ill-gotten arsenal.

For evolution to have formed this system, certain Microstomum must have happened to have selectively digested the Hydra, leaving the nematocysts untouched. Then they also happened to have vectored the nematocysts to the surface and positioned it there. Then certain Microstomum happened to have a feedback loop installed to regulate its diet.

Or consider a sheep parasite known as the brainworm:

The brain worm that reproduces in sheep uses ants to get back into a sheep. The worms get into ants by infecting snails that eat sheep feces. The snails expel tiny worm larvae in a mucus that ants enjoy, and some dozens of worms take up residence in an ant. But this would do them no good if the ant behaved normally; too few ants would be eaten by sheep. Consequently, while most of the worms make themselves at home in an ant’s abdomen, one finds its way to the ants brain and causes the ant to climb up a grass stem and wait to be eaten by a sheep. Ironically, the worm that programs the ant is cheated of happiness in the sheep’s intestine; it becomes encysted and dies.

The whole procedure seems unnecessary. Why do the worm eggs defecated by the sheep not simply hatch and climb up the grass stem to await being eaten by a sheep instead of making the hazardous trip through snail and ant? How could they become adapted to being carried by the ant unless the ant were already programmed to make itself available to be eaten by a sheep?

The list, of course, goes on and on. There is the decoy-fish with its detachable dorsal fin that mimics a smaller fish complete with a dark spot resembling an eye and notch resembling a mouth. The decoy-fish becomes motionless except for the decoy which moves from side to side, causing the “mouth” to open and close. And there is the owl with ears tuned to different frequencies, to better track its prey, and the rattlesnake with heat-sensitive (infrared) sensors to image its prey at night.

Now, a new fossil finding shows just how persistent nature's odd behaviors can be. A carpenter ant (Camponotus leonardi) can be infected by the fungus Ophiocordyceps. Sensitive to the forest temperature and humidity, the fungus must be up off the ground but lower than the forest canopy. It arrives at the desired height by taking over the ant it infects:

The fungus cannot grow high up in the canopy or on the forest floor, but infected ants often die on leaves midway between the two, where the humidity and temperature suit the fungus. Once an ant has died, the fungus sprouts from its head and produces a pod of spores, which are fired at night on to the forest floor, where they can infect other ants.

Scientists led by Hughes noticed that ants infected with the fungus, Ophiocordyceps unilateralis, bit into leaves with so much force they left a lasting mark. The holes created by their mandibles either side of the leaf vein are bordered by scar tissue, producing an unmistakable dumb-bell shape.

It is another fascinating parasitic action that, it would seem, could never be found in the fossil record. But a team of intrepid researchers found a way:

Writing in the journal, Biology Letters, the team describes how they trawled a database of images that document leaf damage by insects, fungi and other organisms. They found one image of a 48m-year-old leaf from the Messel pit that showed the distinctive "death grip" markings of an infected ant. At the time, the Messel area was thick with subtropical forests.

"We now present it as the first example of behavioural manipulation and probably the only one which can be found. In most cases, this kind of control is spectacular but ephemeral and doesn't leave any permanent trace," Hughes said.

And how did evolution design such a Rube Goldberg device? Who knows:

"The question now is, what are the triggers that push a parasite not just to kill its host, but to take over its brain and muscles and then kill it."

He added: "Of all the parasitic organisms, only a few have evolved this trick of manipulating their host's behaviour.

Evolution is truly amazing. It creates in ways we cannot even figure out.

Religion drives science and it matters.

Of Mice and Men: Unconserved Transcription Factors Binding


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You probably learned in high school biology class that the new DNA data has powerfully confirmed evolution. Take any gene and it reveals differences between the species exactly as we would expect. And this sentiment is not limited to high school textbooks. As the Chair of a university Biology department once wrote to me, “DNA sequences provide an absolute and irrefutable record” that evolution is a fact. “Virtually every single gene sequence we examine,” he explained, “can be seen to be represented in closely related species and in more distantly related species with increasing numbers of nucleotide changes as we look at more distant species.” It was, he concluded, “absolute proof, in hard copy, reiterated in every single gene of every single organism.” That is an unfortunately common misrepresentation of the data but the story doesn’t end there. The DNA evidence has falsified several other evolutionary predictions.

Vast stretches of identical DNA segments are found in distant species. Multitudes of differences are found in the DNA of cousin species. Retroviruses that were so often considered to be junk now must be viewed crucial to evolutionary history if Darwin was right. These are some obvious surprises that DNA offered up to evolutionists, but there are more subtle contradictions. One of them, which shows up repeatedly, is the way DNA interacts with proteins.

Consider a recent study of how transcription factor binding is not conserved between mice and men. Transcription factors are proteins that bind to DNA and influence which genes are expressed (transcribed). You may recall that proteins are created by first transcribing genes. So in this complex regulatory network, genes are transcribed to create transcription factor which then return to regulate gene expression.

Evolutionists believe their theory is crucial to biology. Nothing in biology makes sense, they say, except in the light of evolution. We know what questions to ask and where to look only because we have Darwin’s powerful ideas guiding and motivating our research. But transcription factors in the mouse and human do not follow the evolutionary pattern.

Not only do these transcription factors often bind to retrovirus sections of DNA—which evolutionists so often considered to be nothing more than worthless junk—they also usually do not bind in the same DNA locations in spite of their importance. As one commentary explained:

Remarkably, they find that the genomic locations of binding sites for two key regulatory proteins (OCT4 and NANOG) are poorly conserved across species, despite their functional importance in mammalian embryonic stem cell biology. […]

Unexpectedly, only ~5% of binding sites for the two transcription factors OCT4 and NANOG were found in orthologous positions in human and mouse ES cells, suggesting major differences in genome-wide binding profiles between species.

And the story becomes even more contradictory with many of the binding sites were found in non conserved junk DNA:

Remarkably, many of these RABS [repeat-associated binding sites] were found in lineage-specific repeat elements that are absent in the comparison species, suggesting that large numbers of binding sites arose more recently in evolution and may have rewired the regulatory architecture in embryonic stem cells on a substantial scale.

Furthermore, even those genes with conserved transcription factor binding often revealed more detailed differences in the particular binding location:

However, among genes whose OCT4 dependence was conserved between human and mouse, most of the OCT4 binding sites identified were not directly conserved. Instead, the disappearance of a binding site in one species was compensated for by the emergence of a new binding site for the same transcription factor nearby.

The commentary concludes that these findings are consistent with other recent lineage-specific findings:

The notion that some regulatory networks have substantially changed in evolution is also supported by recent independent observations of lineage-specific network rewiring in vertebrate preimplantation embryos and adult liver tissue.

Of course there have been no observations of "network rewiring," lineage-specific or otherwise. This is yet another unfortunate misrepresentation of science. Yes, the new findings are consistent with other recent findings that species differ in subtle yet dramatic ways. But none of this was expected by evolutionary theory. As the paper explains:

Together, these results suggest that many genes have been rewired into the core regulatory network of human embryonic stem cells following the insertion of transposable elements.

So species-specific studies are required:

In contrast, OCT4 and NANOG have very different binding profiles in human and mouse embryonic stem cells, with only ~5% of their sites being homologously occupied. The fact that there is also a limited concordance between regions experimentally observed to be bound and conserved elements, as determined from multispecies sequence alignments, implies that in vivo maps in the relevant species will be important in the study of many mammalian systems. Moreover, to help explain the vast occupancy differences, we showed that species-specific transposable elements have been an important source of new sites in both species.

In other words, evolution doesn’t help explain the findings. What is remarkable is how evolutionists are able to fit even contradictory evidence into their thinking:

we were also able to identify a group of human-specific target genes that show evidence of having been added to the core regulatory network of human embryonic stem cells via the insertion of transposable elements. Although we do not expect all binding events to directly influence gene expression, this data adds important support to a seminal hypothesis on the impact of repeats on the evolution of transcription regulation.

A seminal hypothesis? That is how evolutionists describe unfounded speculation that invokes serendipity to explain unexpected findings.

Genes added to the core regulatory network via the insertion of transposable elements? This is a remarkable example of how evolution has compromised both science and the peer review process. They conclude:

Our results reveal the striking plasticity of the core regulatory network of mammalian embryonic stem cells and the importance that transposable elements have had in facilitating this functional turnover.

This is what happens when evolution is mandated as true. Religion drives science and it matters.