Recent Problems in Evolution - 2004

Table of Contents

Surprisingly rapid growth in Neanderthals

A new study compared the speed of enamel formation in teeth from over 100 Neandertal fossils compared to upper Paleolithic-Mesolithic Homo sapiens (ancient modern humans) and Homo antecessor and Homo heidelbergensis. The upper Paleolithic-Mesolithic H. sapiens exhibited identical dental development compared with modern humans. However, both Homo antecessor and Homo heidelbergensis developed much faster than modern humans while Neandertals developed even faster than their "ancestors." This study provides even more evidence that Neandertals were not ancestral to modern humans.

Ramirez, F. V., R. and J. Maria Bermudez de Castro. 2004. Surprisingly rapid growth in Neanderthals. Nature 428: 936-939 doi:10.1038/nature02428.

Identical DNA that does not carry the information necessary to make a protein.non-coding regions in diverse vertebrate groups

Recent completion of genome sequencing for many diverse vertebrates has revealed long The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequences (at least 200 bp) of DNA that does not carry the information necessary to make a protein.non-coding Deoxyribonucleic acid: the chemical inside the nucleus of a cell that carries the genetic instructions for making living organisms.DNA that are identical or nearly identical. Between humans and mice, 481 of these The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequences are 100% identical. Between humans and dogs, the The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequences are 99% identical. Even between humans and chickens, the The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequences are 95% identical. These The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequences are found on all humans Threadlike "packages" of genes and other DNA in the nucleus of a cell. Different kinds of organisms have different numbers of chromosomes. Humans have 23 pairs of chromosomes, 46 in all: 44 autosomes and two sex chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.chromosomes except 21 and Y. The probability is less than one chance in 1022 of finding even one such The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequence in 2.9 billion bases under a simple model of neutral evolution with independent Replacement of one nucleotide in a DNA sequence by another nucleotide or replacement of one amino acid in a protein by another amino acid.substitutions at each site. Among numerous human individuals, there is almost no The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequence variation (only 6 out of over 100,000 bases). The highly unlikely existence of these identical The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequences indicate that they must absolutely required for survival, since the natural A permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutation rate in humans would have been expected to produce at least 20 times more variation than what is observed.

Bejerano, G., M. Pheasant, I. Makunin, S. Stephen, W. J. Kent, J. S. Mattick, and D. Haussler. 2004. Ultraconserved Elements in the Human Genome. Science 10.1126/science.1098119.

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