Ernst Haeckel (1834-1919), the main propagandist for evolution in Germany, was one of the first scientists to propose a model for the development of multicellular organisms from unicellular ancestors. He proposed that the embryological development of animals today reflects the past development in terms of its evolution. This concept, the recapitulation, states that, "the organic individual repeats during the rapid and short course of its individual development, the most important of the form changes which its ancestors traversed during the long and slow course of their palaeontological evolution according to the laws of heredity and adaptation."ⁱ

Haeckel proposed that organisms go through a series of stages during their embryonic development that resemble the adult forms of their ancestors. But as the facts do not always fit the proposal, Von Baer's suggestion that young stages resemble young ancestral stages enjoys wider acceptance.

Haeckel's theory is largely discredited today on various morphological grounds, but it is also not possible in terms of genetics. Evolution is based on genetic change through mutations over time. Recapitulation requires both retention of the ancestral features and change. Just because homologies appear to exist does not mean that structures are indeed homologous. As Michael Denton points out, homologous organs and structures may develop by radically different embryogenic routes, and "the evolutionary basis of homology is perhaps even more severely damaged by the discovery that apparently homologous structures are specified by quite different genes in different species."ⁱⁱ 

Ernst Haeckel also proposed a mechanism whereby unicellular organisms may have evolved to form multicellular, and eventually multi-layered organisms. This theory is known as the Gastraea Hypothesis. Today, the Planula Hypothesis, a variant of the Gastraea Hypothesis, is more popular, but the problems remain the same as for the Gastraea Hypothesis of Ernst Haeckel.

Using metazoa as a model, Haeckel proposed that multicellular organisms evolved from hypothetical unicellular organisms which he called Cytaea. Eventually these cells remained attached after cell division and a multicellular organism which he termed Moraea evolved. The Moraea gave rise to a jelly-filled hollow ball of cells, called Blastaea which developed an indentation on one side and thus gave rise to the Depaea. Through completion of the indentation, the Depaea gave rise to the Gastraea.

The Gastraea then underwent further differentiation. A third layer of cells developed between the original germ layers. He proposed that this layer, the mesoderm, arose through cellular migration from the outer ectoderm and inner endoderm, thus giving rise to triploblastic organisms (animals with three layers) which would then also have evolved bilateral symmetry after becoming bottom dwellers. Associated with the change in structure there would also have occurred cellular differentiation and specialization, thus giving rise to complex organisms where cells became arranged into organ systems.

For most of these proposed ancestral forms, analogous living forms are presented as evidence for the viability of such organisms. The Cytaea could have resembled living protozoa of the Class Mastigophora, the Moraea represents colonial protozoa such as Pandorina, the Blastaea in turn can be compared to colonial protozoa such as Volvox. The evolution of subsequent stages would have required some complex changes, and it is proposed that the modes of feeding and locomotion of the ancestral types would have affected further differentiation. The bottom dwelling triploblastic animals that developed bilateral symmetry could be compared to present day flatworms.

On the basis of morphology, this theory seems to provide a reasonable pictures of how events may have proceeded during the evolution of multicellular organisms, but at the genetic level, there are serious obstacles. In order to survive as living cells, the early ancestral cells needed a genotype capable of producing all the relevant proteins required to fulfil their physiological and structural needs. These early cells would have had genes coding for all the essential enzymes required to maintain the physiological processes and genes coding for all the necessary proteins involved in the structure or morphology of the cells. Previously, we discussed the problems that would have precluded the evolution of such a cell, but for the sake of this argument, we will assume that such a cell did in fact arise.

Furthermore, it is not too difficult to imagine that a situation could have arisen where cells remained stuck together after cell division, thus resulting in multicellular colonies with the cells embedded in a common matrix. Problems arise, however, when the evolution of cell differentiation and eventual specialization are considered. If the colony arose through cell division, then each of the original colonial cells would have had the same genetic composition, coding for the simplest of cells.

The evolution of specialized cells requires that the different cells also evolve different morphologies and specialized structures dictated by their function. New and diverse morphological and physiological features had to develop as the organisms became more and more complex. The simple colonies would thus eventually consist of more than one cell type. In order to ensure continuity, the genetic changes would have to be transferable to subsequent generations, which requires a far more complex gene arrangement than existed in the unicellular organism. All the variants would have to be located in each cell, with the possibility for selective activation of one or the other batteries of genes.

Assuming that the new genes somehow did evolve, and the organism was endowed with different sets of genes governing the different morphological expressions, there would then be an even greater obstacle to overcome, namely selection. The genes of cells in particular situations would have one set of genes activated and cells in another situation would have the alternative genes activated. As a comparison, in organisms living today, nerve cells have a set of genes activated which distinguish them morphologically and physiologically from liver cells, which have a different part of the genome activated, although both possess the full set of genes.

This differential activation of either the one battery of genes or the other requires a complex system of controlling genes, which would all have to come about by chance, but natural selection can only operate at the level of the phenotype. The chances of all the new genes and controlling genes coming into existence by chance are extremely remote. The probability of just one function gene arising by random chance process is less than one in the number of particles in the entire universe. In fact, it is more probable for an explosion in a woodpile to construct a functional house by chance than it is for just one such new gene to come about by random chance processes. Moreover, one would have to postulate the same scenario thousands of times as cell differentiation increased. This requires a great deal of faith.

The complexity of the genetic requirements for just two different cell types to coexist within an organism is awesome, as can be illustrated by the following example.

If we look at the relationship between a muscle cell and a nerve cell, then it is obvious that there is a great deal of morphological and functional difference between the two. This requires different gene sets to be activated in the two cell types.

Of course, these two cell types would have to cooperate with each other in the living organism in order to be of any value to the organism. Also remember that at the level of the genotype, the processes occur by chance and natural selection can only come into play once the phenotype has been produced. We are not dealing with just a simple genetic variance to achieve these goals, but a host of new genes is required to allow just these two cell types to coexist, let alone the thousands of cell types present in complex multicellular organisms.

For just these two cells, the following genes are required at minimum:

1. Promoter genes enabling the selective activation of either the one or the other. In nerve cells, only those genes which are required for nerve cells will be activated. In muscle cells only those required by muscle cells will be activated.

2. Genes, or DNA sequences, which are sensitive to the environmental cues.

3. Genes to govern the cooperation between the two cell types. This is a very complex arrangement. The two cells would have to link up morphologically in order for the one to activate the other, and there would have to be receptors that enable transfer of information from one to the other.

Where did all these genes come from? The first simple organism required more of these genes which make cooperation between different cells possible. As natural selection does not operate at the level of the genotype, and cannot create anything anyways (only sort out that which is already there), these genes had to come about by either chance or design. Considering the complexity of the system, design seems to be the only option. Haeckel's Gastraea theory is based on a simple morphological sequence that looks good on paper, but is untenable in reality.

Genotype and Phenotype

These are the various ways in which variation is increased today:

1. Built-in variation in the gene pool.

2. Reproductive exchange.

4. Recombination of chromosomes.

All mechanisms that produce variation rely on existing genetic material. None of them were subject to selection, and each of them had to come about by chance or design. 

The faith required to believe that any one of these mechanisms, let alone all of them, came about by chance is extraordinary. If design is the option chosen, then obviously variation of organisms is a hallmark of Creation. God did not then create immutable, unchangeable species, but rather an enormous capacity for change.

The question is no longer whether chance can take place or not, but rather how much change and where the limits are. Also, how rapidly can the change take place and what does it entail? The modern classification system is largely based on resemblances of species on the morphological level, and current biochemical approaches often contradict the morphological approach. Recent examples are inconsistencies between molecular and morphological data in the classification of mice; contradictions in molecular and morphological classification of rodents, rabbits, and primates; and even conflicting classifications in whales.^iii,iv,v

Present-day mechanisms that prevent most species from crossbreeding are cited to have evolved over long periods of time to maintain the integrity of a species. There are, however, many ways in which these could develop rapidly by reshuffling the existing genome. The flexibility of the genome allows for very rapid change that has nothing to do with evolution, but rather with the built-in capacity for variation.

The Biblical concept of a "kind" must also be redefined as a consequence of the above data. Read about the Biblical definition of "kind."

This article adapted from Genesis Conflict by Professor Walter J. Veith, PhD Zoology, renowned author, scientist, and lecturer from South Africa’s Cape Town University. Veith believes that the theory of evolution does not provide a plausible explanation of our origins. His findings are also available on DVD or online through Amazing Discoveries^TM.

i M.W. Strickberger, Evolution (Jones and Bartlett Publishers International, 1996).

ii Michael Denton, Evolution: A Theory in Crisis (London: The Hutchinson Publishing Group, 1985). 

iii P.C. Chevret et al., "Molecular evidence that the spiny mouse (Acomys) is more closely related to gerbils (Gerbillinae) than to true mice (Murinae)," Proceedings of the National Academy of Sciences 90 (1993):3433-3436.

iv D. Graur, "Molecular phylogeny and the higher classification of eutherian mammals" Trends in Ecology and Evolution 8 (1993):141-147. 

v M.C. Milinkovitch, et al., "Revised phylogeny of whales suggested by mitochondrial ribosomal DNA sequences," Nature 361 (1993):346-348.