The diversity of life in the biosphere
O wonder! How many goodly creatures are there heere?
The Tempest, Act V Scene 1
Start is defined by appearance of burrows
that are clearly caused by animals.
- Currently about 590 My ago.
Trichophycus fossil burrows
that define the start of the Cambrian age
Earliest Animal Fossils
early Cambrian -- 570 My
Trilobite Bergeroniellus spinosus
Lena River Gorge, Siberia
(Note dime to indicate size)
“Fossils of trilobites appeared suddenly in the geological record …. If you are tempted by the word “dramatic” then this is the occasion where you could be forgiven for weakening. When you visit a rock section spanning the right bit of the early Cambrian—and there are such profiles in Newfoundland, Mongolia and Siberia—there will be not a sniff of a trilobite as you work your way upwards from one bed to its successor…Then, quite suddenly, a whole Profallotaspis or an Olenellus as big as a crab will pop out into your waiting hands as you split the rock. These are trilobites with lots of segments and big eyes: striking things, not little squitty objects.…You are tempted to cry out: ‘bang!’ And as you continue to collect a foot or so higher into younger strata, the first trilobite will be joined by others, maybe half a dozen or so different species, and all individually distinctive ones at that.”
Richard Fortey, Trilobite!
First Appearance of Animals
Plants (Kingdom Plantae) and
Animals (Kingdom Animalia)?
Both Plants and Animals:
• Many cells
• Reproduce sexually with sperm & egg
• Develop from embryo
(They differ in HOW they form the sperm and egg)
Only Animals: A Genetic Body Plan
homeobox genes = turn on/off gene production
homeotic genes = distinguish regions of cell/body
hox genes = both homeobox and homeotic.
=> Animals have hox genes.
Animals cannot produce all their own food from simple chemicals.
plants can, except for nitrogen)
Common Animal Phyla Originating in Cambrian Explosion
wheel (beating cilia appear rotating)
claw (Arachnida = goddess Arachne)
“arm leg” tentacles
sea urchin skin
(all modern species are vertebrates)
Note: A-19 to A-21 are the Arthropods = “joint-footed”
The Burgess Shale Fossils in the Mid-Cambrian (about 545 My)
Scanning Electron Micrograph
of an Early Cambrian bivalve Crustacean fossil
Moving to Land
Problems Solved by Plants
• How to propagate and survive in extreme conditions.
Solutions: Spores, pollen, seeds.
• How to avoid drying out in the atmosphere?
Cutin (waxy layer on leaves),
Stomata (openings in leaves)
• How to get water and nutrients to plant extremities?
Solutions: roots and vascular system
Note: solution implies a complex control of solutes and a mechanism for water transport.
• How to support weight in air, maintain rigid form
Solution: root system to anchor in ground;
cellulose for low plants (osmotic pressure);
woody tissue for taller plants.
Moving to Land
The Question of “kind”
- How much variation can occur
Two examples with long fossil records:
Working Hypothesis: Variation within a kind is mainly the result of random changes within a stable genetic pool.
• single-celled marine animal with hard (calcium or silicon) skeleton surrounding the nucleus and reproductive apparatus of the cell.
• food-gathering with gelatinous pseudopods that project through skeleton.
• free-floating (planktonic) distributed worldwide.
• fossils found from Cambrian to Present.
A typical radiolarian
“The skeleton of the Radiolaria is developed in such exceedingly manifold and various shapes, and exhibits at the same time such wonderful regularity and delicacy in its adjustments, that in both these respects the present group of Protista excels all other classes of the organic world. For, in spite of the fact that the Radiolarian organism always remains merely a single cell, it shows the potentiality of the highest complexity to which the process of skeleton formation can be brought by a single cell. All that has been brought to pass in this direction by single tissue-cells of animals and plants does not attain the extremely high stage of development of the Radiolaria.”
Ernst Haeckel, Challenger Report on Radiolaria (1887)
Fractal Plant Shapes
These images taken from Michael Barnsley, Fractals Everywhere, Academic Press, 1988.
Fractal Arctic Scene
First appearance about 570 My ago.
Middle Cambrian Trilobite (540 My)
• Compound eyes
• Articulated and segmented exoskeleton
• Jointed legs with gills
• Segmented antennae
Trilobite Internal Body Parts
Trilobite body parts
• Alimentary canal
- mouth, stomach, anus
• Respiratory system with gills
• Circulatory system with heart
• Muscle system
• Simple nerve network
- brain, nerve cord, and ganglia
• Sensory system
- antennas, compound eyes,
touch, sensory pits (smell)
How do we know this Internal detail?
- Pyratized (= fools gold) fossils with soft body details that show up in xrays.
“Some trilobites discovered near Rome, New York have had the hard and soft-body parts replaced by finely crystaline pyrite (FeS2). They display finely detailed external appendages and gills. X-rays reveal fine details of muscular, digestive, circulatory, visual systems. As a result of this providential gift, much is known about trilobite anatomy despite the fact that they have been extinct for 250 million years.”
Rolf Ludvigsen, Fossils of Ontario
Trilobites from Cambrian to Permian
The Trilobite eyes
Kinds of Trilobite eyes:
• Holochroal -- packed cones of silica crystal prisms
• Schizochroal - round compound silica lenses
Devonian Phacops with Schizochroal eyes 
Descartes’ lens (left) and trilobite Crozonaspis (right)
Huygens’ lens (left) and trilobite Dalmanitina (right)
How was the Schizochroal eye created?
Possibility 1: Direct Creation
Possibility 2: Natural Development
- I am inclined to favor Possibility 2.
- Mechanism: Paedomorphosis
= Retention of juvenile features in the adult.
Georges Cuvier (early 1800’s)
“doctrine of Plentitude”
Michael Denton Nature’s Destiny, Chapter 13
“The Principle of Plentitude”
“It appears that every possibility has been realised in the design of image-forming optical devices.”
• Amorphous (hard, soft) and crystalline lenses
• Simple and compound eyes (multiple lenses)
• Focusing and non-focusing
• Reflective and refractive lenses
• Simple and compound lenses
with multiple refractive indices
• Image formation by focussing and by scanning
• A myriad of non-image forming light sensors
• Sensitivity to various parts of the light spectrum
• Passive and active (light generating) eyes
--- This principle carries through in all of biology.
“A comprehensive array of solutions”
--- Not just restricted to “higher” plants and animals
Example: Cnidaria stingers.
• Creation of Plants and Animals is a story of
Gradual buildup of the ecosystem and
Orderly introduction of new species as soon
as the environment is ready.
- Gradual migration to dry land
e.g. Fish -> Amphibians -> Reptiles
unprotected -> protected embryos
e.g. small plants -> large plants
vascula, roots, woody plants
waxy leaves, coated seeds
- Microbe feeders before predators
- Plants before (or with) plant eaters
==> It doesn’t “prove” natural evolution.
• Complex species appear Suddenly in the fossil record
without the precursors or orderly development that
- Animal Body Plans in general
- Trilobites & Crustaceans in particular
• There is evidence for Anticipation of future need in
the appearance of new body plans.
- Trilobite & Crustacean armor
- Trilobite compound lens eye.
• With an adequate gene pool, natural change can
produce a wide range of body shapes and features.
- Radiolarian skeletons
- Trilobite eyes (many varieties)
• Abundant Life:
- The created world uses “every” way to solve the
problems of life.
• A stable ecosystem requires Complete Recycling
- When absent, the system loses balance
- Carboniferous age (must recycle carbon)
- Age of dinosaurs (??)
• The “Nonsense Question” needs answering.
“What are the limits of natural development?”
- There is lots of work to do to answer this.
- The answer can be found in:
- God’s fossil record of his creative activity
+ A deep understanding of genetics and
** I believe that God Intends us to find the
answers, and it is for us to do the hard work.
 Illustration from http://www-white.media.mit.edu/~shers/animals85.gif
 The fossil burrows are known as Trichophycus pedum. In 1991 the International Subcommission on Cambrian Stratigraphy officially set the Cambrian boundary at the first appearance of these fossils. See http://www.uni-wuerzburg.de/palaeontologie/Stuff/casu8.htm.
 from http://www.emory.edu/COLLEGE/ENVS/research/ichnology/
Graphics/Trichophycus.jpg: “a horizontally to obliquely oriented burrow presumed to be produced by a large arthropod”
 From http://www.ucmp.berkeley.edu/arthropoda/
trilobita/bergeroniellus.jpg. Lena River Gorge, Siberia, Early Cambrian. See http://www.ucmp.berkeley.ed/cambrian/aldan.html.
Photo by Jere H. Lipps.
 Lynn Margulis, Five Kingdoms, 3rd. Ed. W.H.Freeman & Co. 1998, Chapter 3 & 5 introduction.
 Colin Tudge, The Variety of Life, Oxford, 2000, p183.
 Following the nomenclature of Lynn Margulis et al, Five Kingdoms, 3rd Ed. W.H. Freeman, 1999. This nomenclature includes all vertebrates as Craniata; some extinct vertebrate species did not have Crania.
 Redrawn from Simon Conway Morris & H.B. Whittington, "The Animals of the Burgess Shale" Scientific American, 1979. Also in Rich&Fenton The Fossil Book, p 115.
 http://www.uni-wuerzburg.de/palaeontologie/cscpic/phosg.jpg SEM micrograph of a hesslandonid phosphatocopine. Oblique view. D. Walossek, Ulm. From the web page “Life in the Cambrian” at http://www.uni-wuerzburg.de/palaeontologie/Stuff/casu8.htm.
 http://www.pbrc.hawaii.edu/bemf/microangela/mradiolo.jpg. One of a series of paintings by MicroAngela.
 Ernst Haeckel, Zoology, Vol XVIII Report on the Radiolaria collected by H.M.S. Challenger, 1887, in Report on the Scientific results of the Voyage of H.M.S. Challenger during the years 1873-1876.
 from http://www.lowtem.hokudai.ac.jp/~frkw/english/
 Paradoxides gracilis Jinetz, Bohemia. approx. 4.5" long. Plate I, Levi-Setti Trilobites
 From http://www.aloha.net/~smgon/trilointernal.htm, Trilobite Internal Anatomy.
 Rolf Ludvigsen, Fossils of Ontario Part 1: the Trilobites, Royal Ontario Museum, 1979, p22.
 Plate 201 Levi-Setti photo by author. Devonian Phacops megalomanicus (Struve), Alnif Morocco