Thursday, July 23, 2015

Mythical Creation Science: What about "Living Fossils"?

This chapter of The New Answers Book 4 (TNA4) edited by Ken Ham is one of the better written chapters in the whole series.  Written by Dr. John Whitmore, the chapter is a rare example of YEC literature that is readable by a scientist.

Some benefits:
  • Dr. Whitmore uses the correct scientific terminology for geographic ages and the scientific names of organisms.  This allows readers to double-check his assertions.
  • He's brave enough to attempt to label the geologic time periods with the YEC periods.  This is pretty handy because entire chunks of the series makes claims without ever grounding them in a geologic time period.
    • The Paleozoic Era (542-250 million years ago(MYA)) is the Early Flood.
    • The Mesozoic Era (250-70 MYA) is Late Flood.
    • The Cenozoic Era (70 MYA - now) is Post-Flood.
  • Unlike most of the authors of the other chapters, he uses YEC assumptions (6,000 year old Earth; the Bible must be right) when talking about YEC ideas.  When talking about science ideas, he actually uses science assumptions (Earth is 4.5 billion years old; Bible isn't a science document). 
Review of Dr. Whitmore's arguments:

Basic overview:
  • A living fossil is a currently extant organism that also has fossils in the same genus or species that show very little change over a long time.
  • States that since YEC believe in a shorter timespan on Earth, living fossils may be more common in a YEC world than a science based world.
Experimental Design:
  • Ran inquiries for 26 phyla in the Paleobology Database ( and counted up the number of genera found that have roots in the Paleozoic (n = 99 species) , Mesozoic (n= 548 species) and Cenozoic (n = 2594 species) Eras. 
  • Made a graph that shows that the number of "living fossils" increases as you move closer to the present.
Arguments against Evolution:
  • If an old Earth existed, how could so many species remain unchanged through the ice ages, mass extinctions and sea levels changes?
  • Refutes Steven Jay Gould's argument that low genetic diversity may leave certain organisms unchanged over long periods of time by arguing that low genetic diversity often leads to extinction and that many diverse families and genera have shown little change over time.
Arguments for YEC
  • The Flood would have killed off a whole lot of families of organisms, so that's why the Paleozoic and Mesozoic Eras have fewer living fossils than the Cenozoic.
  • The Cenozoic is after the flood so fewer organisms would have gone extinct.  Plus, the ark was filled with different "kinds" (similar to the Family level today) that rapidly diversified to fill niches after the Flood.
  • Biologists hate - HATE! - the term "living fossil".  The term implies that the organisms alive today that are also found in the fossil record have not evolved during the intervening time.  A better way to look at a "living fossil" is an organism that hit on a winning combination that hasn't needed much improvement over time AND happened to fossilize well.  The standard example brought up are horseshoe crabs
    • Have they evolved over time?  Yup.  One specific genus has gone extinct (ie - failed to survive a changing environment); three others are alive and well today. 
    • Do they fossilize well? Hell, yeah!  Horseshoe crabs are a giant carapace (exoskeleton) that spends its life in marine sand or mud.  Since exoskeletons resist decay after death and the horseshoe crab is already in prime fossil making territory, we'd be more amazed if we didn't find lots of fossils of these.
    • How certain can scientists be that a genus or species has been evolutionarily unchanged by comparing fossils to living creatures?  If you want to start a brawl, ask the question to a mixed group of paleontologists and biologists.  Paleontologists tend to support lumping fossils that look like living organisms into current genera; biologists tend to prefer splitting them into a different species.  As a trained biologist, I'm biased toward being very cautious about deciding that a fossil that looks like a current species IS the current species.  This is because I use the species definition that requires organisms to be able to interbreed and produce fertile offspring - which we can't determine from fossils.  I concede that I may be overly cautious and cause some extraneous species to be formed.
  • How many species actually remained unchanged?  (Fair warning: I went nerd math crazy.)
    • I went to the same webpage that Dr. Whitmore used - it's a reputable paleobiology site and ran the 26 taxa he listed through the three eras.  
    • From the data in the book, 3% of living fossils are from the Paleozoic, 17% are from the Mesozoic and 80% are from the Cenozoic.
    • This is where I ran into a problem.  He lists 26 kingdoms/phyla that he included in his search, but he reports out the number of genera that are living fossils.  In layman's terms, he listed terms like "cars", "trucks" and "airplanes" and reported out terms like "1987 Yugo GV", "2010 Ford F-150" and "Cessna 350".  I find it hard to believe that he searched each living and extinct known genera individually through this data base; in Plantae alone, that would be over 300,000 species to search.  Also, he only reported out his data in a graph with the total number of living fossils found in each 10 million year period, so I don't have the actual list of species.
    • Here was my solution.  I searched each Era by the 26 kingdom/phyla he reported and collected the number of fossils recorded in the database.  This likely introduced some errors, but I will do my best to be clear about them.
  • These are the total number of fossil records for each Era.  This likely overcounts the number of taxa represented.
  Number of records
Phylum Paleozoic Mesozoic Cenozoic
Annelida 509 974 292
Arthropoda 16333 3200 2583
Brachiopoda 28308 8958 604
Chaetognatha 151 0 0
Chordata 5808 10891 11579
Cnidaria 8174 2728 2168
Coeloscleritophora 296 2 0
Ctenophora 3 0 2
Cyanobacteria 526 165 7
Echinodermata 5358 2756 1183
Ectoprocta 6856 594 1183
Entoprocta 5 0 603
Foraminafera 3585 0 0
Hemichordata 1632 2220 1061
Hyolitha 917 1 0
Mollusca 19360 25620 8749
Nematoda 6 6 18
Nematomorpha 89 0 0
Onychophora 76 0 2
Phoronida 1 12 0
Plantae 2391 3199 1996
Platyhelminthes 1 1 1
Porifera 4089 1286 156
Radiolaria 465 2008 0
Sipuncula 4 1 0
Tardigrada 0 1 110
Sum of records1049436462332297
Number of "living fossils" 99 548 2594
Percentage of fossils made of "living fossils"0.090.858.03

Look at what a tiny fraction of all records the "living fossils" make up!

If my method is accurate, 0.09% of Paleozoic fossils are of "living fossils".  0.85% of Mesozoic fossils and 8% of Cenozoic fossils are living fossils.  These numbers are substantially different from Dr. Whitmore's 3% Paleozoic, 17% Mesozoic and 80% Cenozoic.

Let's say I am off by a power of 10.  This means that the 509 annelid fossils actually make up ~51 genera instead of ~510 genera.

Sum of records 10498.3 6466.3 3232.5
Number of "living fossils" 99 548 2594
Percentage of fossils made of "living fossils" 0.94 8.47 80.2
 Well, that gets the numbers closer - especially the Cenozoic Era.  The Mesozoic is still off by a power of 2 and the Paleozoic is off by a power of 3. 

The problem is that for my math to be off by a power of ten, I have to assume that ALL of the genera that have ever existed have fossilized, the fossils have been recovered and all of those fossils have been entered in the database.    Scientists currently think we have 300,000 species of plants.  The database pulled ~7,600 plant fossils. 

 I feel pretty comfortable with my original numbers.

 So, 0.09% of Paleozoic fossils,  0.85% of Mesozoic fossils, and  8% of Cenozoic fossils are "living fossils".  I find it impossible to reconcile a 99.9% extinction rate over 6,000 years.  Now, over 542 million years, the fact that anything even appears to be a "living fossil" is pretty awesome.



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