MOLECULAR
CLOCKS AND EVOLUTION
Here are
a few copied and pasted annotated references, from a file of references on the
computer I currently use, that may help show the validity of my 6th
post – Science Screw-up No. 1 – posted May 31, 2013. I shudder when I think how many others were
lost in various ways from the overwhelming amount of literature on the topics
that interested me enough to make index cards, entries on earlier computers, and
stacks of journals and clippings still unpacked from moves. Some were cited in the post noted above, but lacked the annotations and/or quotes from the articles.
Because
structure and functions of organisms are the direct targets of natural selection they
can be a better clue to branching pattern of the tree of life until the
generation time of organisms is properly incorporated in the process of tree
construction. Many of my posts rely on this concept for interpreting relationships as well as the views of natural history oriented biologists.
MOLECULAR
CLOCK VARIABLES
Ayala,
Francisco J. 1997. Vagaries of the molecular clock. Proc.
Natl. Acad. Sci. USA, 94:7776-7783.
Found as much as a ten-fold difference between divergence times
estimated by two different Drosophila
genes (GPDH and SOD, or, glycerol-3-phosphate dehydrogenase and super oxide
dismutase). Generation times were
identical in this study so did not affect the rate variation determined.
Bleiweiss,
Robert. 1998. Slow rate of molecular evolution in high-elevation
hummingbirds. Proc. Natl. Acad. Sci. USA, 95:612-616. “A slower rate of single-copy DNA change at
higher elevations suggests that the dynamics of molecular evolution cannot be
separated from the environmental context.” The effect remained “significant
even after taking into account a significant negative association between body
mass and molecular rate.”
Britten,
Roy J. 1986. Rates of DNA sequence evolution differ
between taxonomic groups. Science, 231:1393-1398. “Examination of available measurements shows
that rates of DNA change of different phylogenetic groups differ by a factor of
5. The slowest rates are observed for
some higher primates and..”
Buckley,
Thomas R., Chris Simon, and Geoffrey K. Chambers. 2001.
Exploring among-site rate variation models in a maximum likelihood
framework using empirical data: effects of model assumptions on estimates of
topology, branch lengths, and bootstrap support. Syst.
Biol., 50(1):67-86. variation in
variability across data sets changes estimates, under different model
assumptions, of nodal support and branch length
Campbell,
J. H. 1987. The New Gene and Its Evolution. Pp. 283-309 in Campbell, K. S. W., and M. F.
Day (Eds.). Rates of Evolution. Allen
and Unwin, London. 314 pp.
Rates of evolution pp 303- “To the extent that biological mechanisms
participate in evolutionary change they allow its rate to be programmed
internally as an attribute of the species.”
Clegg, Michael T., Michael P. Cummings, and
Mary L. Durbin. 1997. The evolution of plant nuclear genes. Proc.
Natl. Acad. Sci. USA, 94:7791-7798.
“Analyses of synonymous nucleotide substitution rates for Adh genes in
monocots reject a linear relationship with clock time.” New genes that encode the enzymes
ribulose-1,5-biphosphate carboxylase and alcohol dehydrogenases occurred at ten
times the rate of new genes for alcohol dehydrogenases.
Denver, Dee R.,
Krystalynne Morris, Michael Lynch, Larissa L. Vassilieva, W. Kelley
Thomas. 2000. High direct estimate of the mutation rate in
the mitochondrial genome of Caenorhabditis
elegans. Science, 289:2342-2344.
generation time of 4 days, used 74 lines of single worms, analyzed base
pairs for mutations; 9.7 x 10 to the minus 8 per site per generation or 8.9 per
site per million years. “ . . . revealed
a mutation rate that is two orders of magnitude higher than previous indirect
estimates,”
Field,
Katharine G., Gary J. Olsen, David
J. Lane, Stephen J. Giovannoni, Michael T.
Ghiselin, Elizabeth C. Raff, Norman R. Pace, and Rudolf A. Raff. 1988.
Molecular phylogeny of the animal kingdom. Science,
239:748-753. “Coelomates are thus
monophyletic, and they radiated rapidly into four groups: chordates,
echinoderms, arthropods, and eucoelomate protostomes.” “The use of cellular RNA for these studies
guarantees that sequences will represent commonly transcribed RNA genes, not
minor or inactive genes. The method
provides sequences in the most conservative portions of the 18S rRNA molecule, which are the most
useful for broad phylogenetic comparisons.” see following sentence page 748
also [“For distantly related organisms, it is not possible to establish
homology between nucleotides in the rapidly evolving portions of the molecule;
thus, even if the entire 18s rRNA sequence is known, only some parts of it can
be used for phylogenetic inference.”].
Study was based on 18S
ribosomal RNA sequences. Pogonophoran used was a thermal-vent species, annelids
were a polychaete and an earthworm, chordates were a tunicate, amphioxus, a
frog, and a human.
Fitch,
Walter M., Robin M. Bush, Catherine A. Bender, and Nancy J. Cox. 1997.
Long term trends in the evolution of H(3) HA1 human influenza type A. Proc.
Natl. Acad. Sci. USA, 94:7712-7718.
Variation of replacement substitution rate of codons as much 7.2 times
greater in a hypervariable one. Rate
lowest in trunk codons, intermediate in twigs, and greatest in tip
branches. [thought added 2/6/03 – might be an
expression of selection against deleterious substitutions eliminated more
effectively due to time as one goes to older twigs and trunk. (jge) I had just
been thinking of that while trying to improve on method of calibrating
molecular clocks with generation time corrections for both calibration species
(if not from lines studied) and generation time difference of branch species (A
correction of up to 199.999% of uncorrected bifurcation value is needed if
generation time of shortest lived species was used; whereas estimate could need
reduction of up to 99.999% if based on longest lived species); therefore two
separate generations time corrections must be considered if calibration species
is a third species; no correction for generation time is needed if all three
have same generation time.]
Gillooly,
James F., Andrew P. Allen, Geoffrey B. West, and James H. Brown. 2005.
The rate of DNA evolution: effects of body size and temperature on the
molecular clock. Proc. Natl. Acad. Sci. USA, 102:140-145. support a single molecular clock, “but that
it “ticks” at a constant substitution rate per unit of mass-specific metabolic
energy rather than per unit of time.”
Keightley,
Peter D., and Adam Eyre-Walker.
2000. Deleterious mutations and
the evolution of sex. Science, 290:331-333. [13 Oct 2000]
Deleterious mutations were eliminated more rapidly in short generation
time species. The study did not support
(MD) “mutational deterministic” hypothesis for obligate sexuality.
Kimura,
Motoo, and Tomoko Ohta. 1971. On the
rate of molecular evolution. J. Molec. Evolution, 1:1-17. citing
various sources for a rate of about one centipauling for histones to four
paulings for Fibrinopeptide A. (1
pauling = “rate of substitution of 10 [to minus 9] per amino acid site per
year.)
Kuman,
Sudhir, and S. Blair Hedges. 1998. A molecular timescale for vertebrate
evolution. Nature, 392:917-920. [30 Apr 1998] In estimates of divergence times using
different genes, a standard error of about 10% was found using ten genes, but
the standard error was only 5% if 50 genes were used and 3% with use of 100
genes. Their study used 658 genes
distributed among 207 species of vertebrates (mostly mammals). [note added 11/25, 2014 - this shows the ability of statistical
analysis to give a more precise wrong answer, if a uniform rate premise is
wrong – a point of my May 31, 2013 post; see Maley and Marshall, 1998 below
also]
Laird,
Charles D., Betty L. McConaughy, and Brian J. McCarthy. 1969.
Rate of fixation of nucleotide substitutions in evolution. Nature,
224:149-154. a ten-fold higher rate of nucleotide sequence variation for
rodents compared to artiodactyls is found when time estimates are in years “This difference diminishes if generations,
rather than years, represent the appropriate interval of evolutionary
divergence.”
Maley,
Laura E., and Charles R. Marshall.
1998. The coming of age of
molecular systematics. Science, 279:505-506. “Growing evidence suggests that phylogenies
of animal phyla constructed by the analysis of 18S rRNA sequences may not be as
accurate as originally thought.” . . .
“In extreme cases the inferred relationships between groups may change
when different representative species are used.” . . “as the amount of data
analyzed increases, so does the apparent statistical support for an incorrect
phylogenetic tree.”
Mishmar,
Dan, Eduardo Ruiz-Pesini, Pawel Golik, Vincent Macaulay, Andrew G. Clark, Seyed
Hosseini, Martin Brandon, Kirk Easley, Estella Chen, Michael D. Brown, Rem I.
Sukernik, Antonel Olckers, and Douglas C. Wallace. 2003.
Natural selection shaped regional mtDNA variation in humans. Proc.
Nat. Acad. Sci. USA, 100(1):171-176.
p. 171-“multiple amino acid changes found in ATP6, cytochrome b, and
cytochrome oxidase I appeared to be functionally significant. From these analyses we conclude that
selection may have played a role in shaping human regional mtDNA variation and
that one of the selective influences was climate.” P. 176 –“If selection has played an important
role in the human mtDNA lineages, then the rate of mtDNA molecular clock may
not have been constant throughout human history. If this is the case, then conjectures about
the timing of human migrations may need to be reassessed.”
Miyamoto,
Michael M., Jerry L. Slightom, and Morris Goodman. 1987.
Phylogenetic relations of humans and African apes from DNA sequences in
the ψη-globin region. Science, 238:369-373. “. . the slowdown in the rate of sequence
evolution evident in higher primates is especially pronounced in humans.”
Mooers,
Arne Ø., and Edward C. Holmes.
2000. The evolution of base
composition and phylogenetic inference. Trends in Ecology and Evolution (TREE),
15(9):365-369. “. . , in the early 1990s, phylogeneticists discovered that the
variation in GC content among organisms could wreak havoc on attempts to
reconstruct evolutionary history. This
was because the tree-building techniques then in use often grouped together
unrelated species with similar GC content.”
Nichols,
Richard. 2001. Gene trees and species trees are not the
same. Trends in Ecology and Evolution (TREE), 16(7):358-364. different genes may evolve at different
points in time in the same lineage giving different times of separation if only
one is considered to calculate divergence time
Shaw, Kerry
L. 2002.
Conflict between nuclear and mitochondrial DNA phylogenies of a recent
species radiation: What mtDNA reveals and conceals about modes of speciation in
Hawaiian crickets. Proc. Natl. Acad. Sci. USA, 99:16122-16127. “The discrepancy between mtDNA and nDNA
phylogenies reveals that speciation histories based on mtDNA alone can be
extensively misleading.”
Simmonds,
P., and D. B. Smith. 1999. Structural constraints on RNA virus
evolution. Journal of Virology, 73(7):5787-5794. Evidence of rate of mutations variation with
nucleotide location in relation to secondary structure of GB virus C. In this case, molecular clock assumptions are
incorrect.
Joseph Engemann Kalamazoo, Michigan November 25, 2014