Table 1: Species generation times used in this study
Generation
Reference
Comments
time used
Anopheles gambiae (aga)
10 days
1
Ranges from 5-14 days
Egg to emergence of Drones is 24 days
Apis mellifera (ame)
40 days
2
and it reaches sexual maturity 12-14
days after emergence
Arabidopsis thaliana (ath)
45 days
3
Gestation period of 9 months + 1 year to
Bos taurus (bta)
2 years
4
sexual maturity
Caenorhabditis elegans (cel)
3 days
3
Gestation period of 2 months + 6-12
Canis familiaris (cfa)
11 months
4
months to sexual maturity
Danio rerio (dre)
3 months
3
Asexual reproduction is 4 hrs. Sexual
reproduction (spore-spore) - 3 days.
However asexual reproduction is
Dictyostelium discoideum (ddi)
8 hrs
3,5 common and sexual reproduction occurs
only upon starvation (See ref 5). Four
hours was chosen arbitrarily by giving
more weight to asexual reproduction.
Drosophila melanogaster (dme)
12 days
3
Entamoeba histolytica (ehi)
10 hrs
6
Gallus gallus (gga)
5 months
3
Homo sapiens (hsa)
20 years
7
Gestation period of 21 days + 5-7 weeks
Mus musculus (mmu)
65 days
4
to sexual maturity
Crop duration for rice varieties ranges
Oryza sativa (osa)
4.5 months
8
from 3 - 9 months
Saccharomyces cerevisiae (sce)
2.5 hrs
9
Strongylocentrotus purpuratus(spu) 1 year
3
Asexual reproduction is the
predominant mode of reproduction and
takes about 1.5 hrs. Sexual
reproduction from zygote to zygote
Tetrahymena thermophila (tth)
3 hrs
3, 10 ranges from 1day to14 days and this
occurs once in ~ 100 generations See ref
10. Three hours was chosen arbitrarily
by giving more weight to asexual
reproduction.
Tribolium castaneum (tca)
70 days
11
Ranges from 7-12 weeks
Trypanosoma cruzi (tcr)
1 day
12
Xenopus tropicalis (xtr)
4 months
13
Species (abbreviation)
Figure 1. Neighbor-joining tree was constructed using 32 orthologous protein coding
genes common to all 20 species. The orthology was determined by reciprocal BLAST
searches of the proteomes. The tree was constructed using Poisson corrected distance.
The topology and branch lengths were similar when different gamma parameters were
used. This tree topology and branch lengths were used for independent contrast analysis
using the CONTRAST package of PHYLIP (14).
Figure 2. This tree is based on previously published phylogenies of mammals (15),
insects (16), coelamates (17) and basal eukaryotes (18). The relationships of the other
clades are well known (see, Tree of life web project, http://www.tolweb.org). The
polytomies are due to the uncertain relationship among basal eukaryotes (18). The
independent contrast analysis was conducted using the software CAIC (19). This
program assumes that the ages of taxa are proportional to the number of species they
contain and uses an algorithm from Grafen (20) to obtain the relative length of each
branch.
Table 2. Results of independent Contrast Analysis
Contrast 1 Contrast 2
No. of
contrasts Slope Pearson r P - value
PHYLIP
Gen. time a
ENC'
ENC'
Gen. time
19
19
-0.15
-3.39
-0.72
-0.72
0.0003
0.0003
CAIC
Gen. time
ENC'
ENC'
Gen. time
15
15
-0.2
-2.97
-0.78
-0.78
0.0004
0.0004
ENC'
Std.Devb
15
-0.28
0.10
Gen. time
Std.Dev
15
1.2
0.11
c
Gen. time
Std.Dev
15
1.4
0.23
a
– Log transformed values of generation time and ENC' estimates.
b
– Square root of the sum of the branch lengths in a given node.
c
– After excluding two outliers.
0.71
0.69
0.39
References
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Link: http://www.cdc.gov/malaria/biology/mosquito/
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3. National Institute of Health, USA
Links: Arabidopsis - http://www.nih.gov/science/models/arabidopsis/index.html
Worm, fruit fly and Zebra fish - http://www.nih.gov/science/models/nmm/appc1.html
Dictyostellium and Tetrahymena - http://www.nih.gov/science/models/nmm/appc2.html
Chicken - http://www.nih.gov/science/models/nmm/appc3.html
Sea urchin - http://www.nih.gov/science/models/nmm/appc4.html
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