An extremely common misperception is that natural selection and evolution are the same thing. In fact, Haeckel is one of many thinkers who believed that all species were historical entities (lineages) but did not share Darwin's enthusiasm for natural selection as the main mechanism for generating the diversity of the biological world. Haeckel instead believed that the environment acted directly on organisms, producing new races (a version of Lamarckism). The survival of the races did depend on their interaction with the environment, a weak form of natural selection. Haeckel's mechanism of change required that formation of new characters diagnostic of new species occured through progressive addition to the developmental trajectory. For example, most metazoans go through a developmental stage called a gastrula -- a ball of cells with an infolding that later forms the gut. Haeckel thought that at one time an organism called a "gastraea" existed that looked much like the gastrula stage of ontogeny. This hypothesized ancestral metazoan gave rise to the rest of the multi-celled animals.

The "law of recapitulation" has been discredited since the beginning of the twentieth century. Experimental morphologists and biologists have shown that there is not a one-to-one correspondence between phylogeny and ontogeny. Although a strong form of recapitulation is not correct, phylogeny and ontogeny are intertwined, and many biologists are beginning to both explore and understand the basis for this connection.

The Equation of Recapitulation:

Square of ontogenic time = 288,000 ธ phylogenic time

1. Phylogenic Times (P) are 6 times less than the previous period.

P₁ = P₀ ธ 6 = 20

2. Ontogenic Times (O) are ึ 6 times greater than the previous period.

O₁ = O₀ ด ึ 6 = 120

Square both side of the equation.

O₁² = O₀² ด 6

3. Multiply equation 1 with equation 2, we get

P₁ ด O₁² = P₀ ด O₀² = 20 ด 120 ด 120 = 288,000

4. By generalization

P_i ด O_i² = 288,000 for Homo sapiens

O_i² = 288,000 ธ P_i

Square of ontogenic time = 288000 ธ Phylogenic time

5. Time in evolution can be calculated if we know the exact time in embryology.

P_i = 288,000 ธ O_i²

 

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How to prove or disprove this idea.

This equation should apply to all mammals alike.

Longer gestation period means longer life span.

To be precise, time from fertilization to walking can be used to calculate life span.

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