Structures do not evolve before there is a need for them
A fundamental premise of evolutionary theory is that evolution has no foresight. It is a blind process responding to current, not future, needs. This means that biological structures do not evolve before they are needed. But many examples of this have been discovered in recent years. For instance, in the embryonic stages of a wide variety of organisms, the development of the vision system is orchestrated by similar control genes known as transcription factors. As one paper explained, “All eyes, invertebrate and vertebrate, develop through a cascade of similar transcription factors despite vast phylogenetic distances.” (Wake, Wake and Specht) Because these transcription factors are so prevalent across the evolutionary tree, they must have evolved in the very early stages of evolution, in an early common ancestor. But that was before any vision systems had evolved. The vision system is just one of several such examples showing that the genetic components of many of today’s embryonic development pathways must have been present long before such pathways existed. Evolutionists now refer to the appearance of these genetic components, before they were used as such, as preadaptation:
Genome comparisons show that the early clades increasingly contain genes that mediate development of complex features only seen in later metazoan branches. … The existence of major elements of the bilaterian developmental toolkit in these simpler organisms implies that these components evolved for functions other than the production of complex morphology, preadapting the genome for the morphological differentiation that occurred higher in metazoan phylogeny. (Marshall and Valentine)
Such preadaptation extends beyond embryonic development. For example, several key components of the human brain are found in single-celled organisms called choanoflagellates. Therefore these key components must have evolved in single-celled organisms, long before animals, brains and nerve cells existed. As one evolutionist explained, “The choanoflagellates have a lot of precursors for things we thought were only present in animals.” (Marshall)
Another example is the molecular machines for protein transport across the mitochondria inner membrane which must have evolved long before mitochondria existed. (Clements et. al.) As one evolutionist explained, “You look at cellular machines and say, why on earth would biology do anything like this? It’s too bizarre. But when you think about it in a neutral evolutionary fashion, in which these machineries emerge before there’s a need for them, then it makes sense.” (Keim)
References
Clements, A., D. Bursac, X. Gatsos, et. al. 2009. “The reducible complexity of a mitochondrial molecular machine.” Proceedings of the National Academy of Sciences 106:15791-15795.
Keim, Brandon. 2009. “More ‘Evidence’ of Intelligent Design Shot Down by Science.” Wired Aug. 27. http://www.wired.com/wiredscience/2009/08/reduciblecomplexity/
Marshall, Michael. 2011. “Your brain chemistry existed before animals did.” NewScientist September 1.
Marshall C., J. Valentine. 2010. “The importance of preadapted genomes in the origin of the animal bodyplans and the Cambrian explosion.” Evolution 64:1189-1201.
Wake D., M. Wake, C. Specht. 2011. “Homoplasy: from detecting pattern to determining process and mechanism of evolution.” Science 331:1032-1035.
A fundamental premise of evolutionary theory is that evolution has no foresight. It is a blind process responding to current, not future, needs. This means that biological structures do not evolve before they are needed. But many examples of this have been discovered in recent years. For instance, in the embryonic stages of a wide variety of organisms, the development of the vision system is orchestrated by similar control genes known as transcription factors. As one paper explained, “All eyes, invertebrate and vertebrate, develop through a cascade of similar transcription factors despite vast phylogenetic distances.” (Wake, Wake and Specht) Because these transcription factors are so prevalent across the evolutionary tree, they must have evolved in the very early stages of evolution, in an early common ancestor. But that was before any vision systems had evolved. The vision system is just one of several such examples showing that the genetic components of many of today’s embryonic development pathways must have been present long before such pathways existed. Evolutionists now refer to the appearance of these genetic components, before they were used as such, as preadaptation:
Genome comparisons show that the early clades increasingly contain genes that mediate development of complex features only seen in later metazoan branches. … The existence of major elements of the bilaterian developmental toolkit in these simpler organisms implies that these components evolved for functions other than the production of complex morphology, preadapting the genome for the morphological differentiation that occurred higher in metazoan phylogeny. (Marshall and Valentine)
Such preadaptation extends beyond embryonic development. For example, several key components of the human brain are found in single-celled organisms called choanoflagellates. Therefore these key components must have evolved in single-celled organisms, long before animals, brains and nerve cells existed. As one evolutionist explained, “The choanoflagellates have a lot of precursors for things we thought were only present in animals.” (Marshall)
Another example is the molecular machines for protein transport across the mitochondria inner membrane which must have evolved long before mitochondria existed. (Clements et. al.) As one evolutionist explained, “You look at cellular machines and say, why on earth would biology do anything like this? It’s too bizarre. But when you think about it in a neutral evolutionary fashion, in which these machineries emerge before there’s a need for them, then it makes sense.” (Keim)
References
Clements, A., D. Bursac, X. Gatsos, et. al. 2009. “The reducible complexity of a mitochondrial molecular machine.” Proceedings of the National Academy of Sciences 106:15791-15795.
Keim, Brandon. 2009. “More ‘Evidence’ of Intelligent Design Shot Down by Science.” Wired Aug. 27. http://www.wired.com/wiredscience/2009/08/reduciblecomplexity/
Marshall, Michael. 2011. “Your brain chemistry existed before animals did.” NewScientist September 1.
Marshall C., J. Valentine. 2010. “The importance of preadapted genomes in the origin of the animal bodyplans and the Cambrian explosion.” Evolution 64:1189-1201.
Wake D., M. Wake, C. Specht. 2011. “Homoplasy: from detecting pattern to determining process and mechanism of evolution.” Science 331:1032-1035.
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