Thursday 30 July 2015

Evidence is a funny thing.

Here are a series of Tweets that have had extra details removed.  Most of the excised details are of the original poster's ID and the IDs she was responding to.
Tami ‏@Tam...yama  Jul 27
Genetic entropy &  information & code in DNA refute biological evolution.
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No mechanism exists that adds novel function info to DNA that allows, say, fish to evolve to amphibians or ...
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.. reptiles to birds ... or invertebrates to veryebrates. So my rejection of evolution is EVIDENCE-based.
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Here is my attempt at a full-length response regarding evidence.  I believe the results of the Lenski experiment show how a duplication mutation followed by local mutations can add novel functions to DNA.

Evidence is a funny thing.

I want to start this discussion with some examples of events where we don't expect evidence of their occurrence.  I will start with New Testament examples so even before that, let me start with a reminder that where evolution is concerned, neither I personally nor the theory of Evolution is anti-Christian or anti-religion.  The Roman Catholic Church has long accepted evolution with a wonderful sentence on the subject from Pope John Paul II.
 "The convergence, neither sought nor provoked, of results of studies undertaken independently from each other constitutes in itself a significant argument in favor of this theory."

In addition, around 13,000 (13,008 signatures, as noted on my Birthday - probably not related) clergy in the USA have signed a letter stating that they see no conflict between their religious beliefs and the theory of Evolution.

OK, miracles in the New Testament where we do not expect evidence.  First, the miracle of the Loaves and Fishes.

Jesus Feeds the Five Thousand13 When Jesus heard what had happened, he withdrew by boat privately to a solitary place. Hearing of this, the crowds followed him on foot from the towns. 14 When Jesus landed and saw a large crowd, he had compassion on them and healed their sick.
15 As evening approached, the disciples came to him and said, “This is a remote place, and it’s already getting late. Send the crowds away, so they can go to the villages and buy themselves some food.”
16 Jesus replied, “They do not need to go away. You give them something to eat.”
17 “We have here only five loaves of bread and two fish,” they answered.
18 “Bring them here to me,” he said.
19 And he directed the people to sit down on the grass. Taking the five loaves and the two fish and looking up to heaven, he gave thanks and broke the loaves. Then he gave them to the disciples, and the disciples gave them to the people.
20 They all ate and were satisfied, and the disciples picked up twelve basketfuls of broken pieces that were left over.
21 The number of those who ate was about five thousand men, besides women and children.
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It would be crazy for anyone, believer or not, to go to Bethesda, apparently on the Jordan River,  and look for evidence of the miracle but let's imagine someone tried.  They might find fish bones - but this is on the side of a river, so bones would hardly be surprising.  Maybe, if we wanted to stretch a point to a ridiculous extent, we could imagine looking for the bones of a thousand or so fish, all in the same location and all with enough good DNA in them to show they were somehow clones of each other.  That might show they were perfectly replicated in the miracle.
This excludes the possibility, though, of God choosing to make the fish pleasing each individual taste so all had their favorite, whether it be bass, trout, carp or well, fish that actually live in the Middle East rather than my native Canada.
So, we have a situation where finding the (far-fetched) evidence would defend the claims of the miracle but not finding the evidence does no injury to those claims.
The same might be said regarding evidence of Mary's virginity during her pregnancy.  'nough said.
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ADDED LATER:
Snopes on The Lost Day (This is about the claim that NASA engineers working to organize their satellites for long periods of time, had made a computer program to plan for a hundred or a thousand years.  But the computer broke down and the reason was, there was a missing day.  This is crazy as Snopes explains)
Regardless of the amount of time involved, the discovery of a "missing" period of time remains implausible. If the sun had indeed stood still for a day a few millennia ago, we would have no way of determining that fact through astronomic observations today. We have no frame of reference, no cosmic calendar or master clock to check against to see if we're overdrawn at the Bank of Time. The concept described here would be like giving someone a non-functioning clock and asking him to determine how much time had elapsed since the clock had stopped running. One could note the positions of the hands on the dial and make a reasonable guess about what the time of day was when the clock stopped running, but without knowing whether that time was A.M. or P.M., and without knowing the calendar date on which stoppage occurred, one could not possibly make any reasonable estimate about how long ago the clock stopped
Read more at http://www.snopes.com/religion/lostday.asp#I5UKJbwmB6WfiB9k.99
AIG agrees as does ChristianAnswers.
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The point is, a lack of evidence for an event is not evidence of a lack of that event.

So now we turn to transitional fossils and their apparent lack.
As before, although I just said we would look at evidence, let's first look at what 'transitional fossils' are or should be if they exist.  A transitional fossil is an example of a once-living creature that has features of two different groups.  I will use 'Archaeopteryx' as an example to demonstrate what a transitional fossil is and isn't.
archaeopteryx appears to have characteristics of both dinosaurs and birds.  There are some features that are too technical for me to comment on but a toothy beak (dino), long, bony tail (dino) and feathers (bird) are good starting points.
Was Archaeopteryx the actual transitional species?  There is no way to be sure but it seems likely not.  The stony remains that hold the shape of the original bones do not have DNA and I wonder if full DNA would even help - we would need good exemplars of several dinosaur species DNA to compare it with.  The stony remains can only tell us that an animal existed that had the features expected of a transitional species.  Is Archaeopteryx the grandfather or the great-uncle of modern birds? Impossible to say.
For one thing, it appears that Archaeopteryx is too young.  There are more fully bird fossils deeper and older than Archaeopteryx.  Does this mean Archeop (please forgive the short-form, I am becoming tired of the full name.  Expect more of the like to come.) didn't exist before birds.  No.  a transitional fossil is like a single photograph.  I have a photo of me paddling a canoe in Georgian Bay dated to 1999 but I existed for 32 years before that and at least 16 -as of this writing - more after that.  A transitional fossil doesn't lock in the full period of a species' existence.  And we wouldn't expect it to.  The more common a species is, among other factors, means a greater likelihood of fossilization.  When a species first evolves and as it goes extinct, the numbers are going to be smaller.

Now for the 'other factors' mentioned in the paragraph above.  Fossils are rare.  This is not a desperate hope stated by paleontologists to explain away the claimed lack of evidence but a fact.  Let me defend this fact.
First, soft bodied and small animals are less likely to be fossilized.  bones, especially large ones, are more likely to last long enough to be buried in sediment and be fossilized.  A soft bodied animal or soft tissue of a bony animal is more likely to be eaten or rot away.  Such fossils are found but in lesser numbers.  This is a (n entirely reasonable) fact.

Second, many animals die where fossilization is unlikely.  Yes, I did choose the 'weasel-word' "many".  I can't say whether this is a majority or not, but i believe it is.  It is at least a large number, however else you define it.  Fossilization in a jungle is rare - the warm, humid condition encourage the life of ants and other scavengers even smaller.  a remarkable fact I recently learned is that the first Chimpanzee fossil ever found we found only eight years ago (in 2006).  To my knowledge, there are only around six chimpanzee individuals that have fossilized that we know of.  Another example is that of buried soldiers from World War 2.  Many died and were buried in France and after decades past some Americans have wanted their heroes to come home.  The graves were dug up but often no bodies -and seldom even cloth or belt buckles - are found.  Forty years after a large bodied vertebrate, buried below the active biological layer of soil and the remains are gone.

In the TV show for the book, Your Inner Fish, Dr Niel shubin describes fossil collecting in the American North-East coast.  At one place with huge tides, he described going onto the sea bed at low tide, finding many new fossils, trying to collect a few before being forced away by the returning tide. The next day, many of the fossils seen the day before are worn away and new ones are visible.  The life of fossils on the rock surface in this region can be measured in days or hours.

I haven't actually defended evidence of evolutionary change in this blog post but I hope I have defended the state of evidence and shown that the fossil evidence, weak as it might be (I think it is actually pretty good although that might be the subject to a later post), is satisfactory and not a deal-breaker for evolution.

Tuesday 21 July 2015

more feathered dinosaurs

Sci Am has the details.  Below is an image from the link - deliberately shrunk a little - if you want full quality, follow the link.