curupira
08-31-2013, 01:29 AM
An interesting subject, they are our closest cousins among living animals... Would anyone help me in finding more recent studies?
I went to the zoo a couple of days ago and I found them amazing, great apes are definitely the most interesting animals IMO. Their behaviour can be quite helpful in understanding ourselves.
The most evident difference is on chromosome 2, it became fused in modern humans (as well as in Neanderthals and Denisovans).
http://upload.wikimedia.org/wikipedia/commons/0/06/Humanchimpchromosomes.png
http://en.wikipedia.org/wiki/Chimpanzee_genome
This is a study from 2005:
The chimpanzee genome sequence is a long-awaited milestone, providing opportunities to explore primate evolution and genetic contributions to human physiology and disease. Humans and chimpanzees shared a common ancestor ∼5-7 million years ago (Mya). The difference between the two genomes is actually not ∼1%, but ∼4%—comprising ∼35 million single nucleotide differences and ∼90 Mb of insertions and deletions. The challenge is to identify the many evolutionarily, physiologically, and biomedically important differences scattered throughout these genomes while integrating these data with emerging knowledge about the corresponding “phenomes” and the relevant environmental influences. It is logical to tackle the genetic aspects via both genome-wide analyses and candidate gene studies. Genome-wide surveys could eliminate the majority of genomic sequence differences from consideration, while simultaneously identifying potential targets of opportunity. Meanwhile, candidate gene approaches can be based on such genomic surveys, on genes that may contribute to known differences in phenotypes or disease incidence/severity, or on mutations in the human population that impact unique aspects of the human condition. These two approaches will intersect at many levels and should be considered complementary. We also cite some known genetic differences between humans and great apes, realizing that these likely represent only the tip of the iceberg.
http://genome.cshlp.org/content/15/12/1746.long
A study on the mtDNA of Chimpanzees (2010):
Evolutionary History of Chimpanzees Inferred from Complete Mitochondrial Genomes
Introduction
Primate evolution is a topic of widespread interest and frequent investigation in large part because of a desire to understand the details and context of human evolution. Humans are most closely related to the two species comprising the genus Pan: Pan troglodytes (the common chimpanzee) and P. paniscus (the bonobo). Deliberation over the appropriate classification of P. troglodytes into biologically relevant groups is ongoing (Gonder et al. 2006), and the timing of significant divergence events within the species is not resolved (e.g., Won and Hey 2005; Becquet et al. 2007; Hey 2010). An accurate timescale of evolution of our closest relatives is fundamental to investigating a range of important questions, from the emergence of pathogens to the nature of the adaptive changes that have occurred within humans and apes. [...]
The rate of evolution in the chimpanzee-plus and bootstrapped-chimpanzee analyses were calibrated by applying lognormally distributed priors about robustly supported estimates of divergence events at three internal nodes (Raaum et al. 2005): Old World monkey–hominoid (23 Ma), orangutan–African ape (14 Ma), and chimpanzee–human (6 Ma). [...]
e used lognormal calibration distributions with lognormal means of zero and lognormal standard deviations of 0.56, and we offset these distributions by 22 Ma (Old World monkey–hominoid), 13 Ma (orangutan–African ape), and 5 Ma (chimpanzee–human). This ensured that the median values of the sampled distributions were equal to and the mean values were slightly greater than the respective 23, 14, and 6 Ma point calibrations used by Raaum et al. (2005). [...]
In this study, we performed the first mtDNA-based analysis of the timing and topology of diversification within the P. troglodytes lineage using 24 newly derived full-length chimpanzee mitochondrial genomes. By simultaneously incorporating speciation and population-level demographic parameters into our analyses, we also obtained tMRCA estimates of major primate lineages back to the most recent common ancestor preceding the split of New World monkeys from Old World monkeys and the Great Apes.
http://mbe.oxfordjournals.org/content/28/1/615.full (the study can be downloaded in pdf format via this link)
Chimpanzee mtDNA:
http://i39.tinypic.com/33445y1.jpg
Chimpanzees are our closest cousins among living animals, we diverged from them ~ 6 million years ago. Gorillas are our second closest cousins, and Orangutans the third:
http://i41.tinypic.com/2q8yiit.png
http://www.nature.com/nature/journal/v469/n7331/full/nature09687.html
I went to the zoo a couple of days ago and I found them amazing, great apes are definitely the most interesting animals IMO. Their behaviour can be quite helpful in understanding ourselves.
The most evident difference is on chromosome 2, it became fused in modern humans (as well as in Neanderthals and Denisovans).
http://upload.wikimedia.org/wikipedia/commons/0/06/Humanchimpchromosomes.png
http://en.wikipedia.org/wiki/Chimpanzee_genome
This is a study from 2005:
The chimpanzee genome sequence is a long-awaited milestone, providing opportunities to explore primate evolution and genetic contributions to human physiology and disease. Humans and chimpanzees shared a common ancestor ∼5-7 million years ago (Mya). The difference between the two genomes is actually not ∼1%, but ∼4%—comprising ∼35 million single nucleotide differences and ∼90 Mb of insertions and deletions. The challenge is to identify the many evolutionarily, physiologically, and biomedically important differences scattered throughout these genomes while integrating these data with emerging knowledge about the corresponding “phenomes” and the relevant environmental influences. It is logical to tackle the genetic aspects via both genome-wide analyses and candidate gene studies. Genome-wide surveys could eliminate the majority of genomic sequence differences from consideration, while simultaneously identifying potential targets of opportunity. Meanwhile, candidate gene approaches can be based on such genomic surveys, on genes that may contribute to known differences in phenotypes or disease incidence/severity, or on mutations in the human population that impact unique aspects of the human condition. These two approaches will intersect at many levels and should be considered complementary. We also cite some known genetic differences between humans and great apes, realizing that these likely represent only the tip of the iceberg.
http://genome.cshlp.org/content/15/12/1746.long
A study on the mtDNA of Chimpanzees (2010):
Evolutionary History of Chimpanzees Inferred from Complete Mitochondrial Genomes
Introduction
Primate evolution is a topic of widespread interest and frequent investigation in large part because of a desire to understand the details and context of human evolution. Humans are most closely related to the two species comprising the genus Pan: Pan troglodytes (the common chimpanzee) and P. paniscus (the bonobo). Deliberation over the appropriate classification of P. troglodytes into biologically relevant groups is ongoing (Gonder et al. 2006), and the timing of significant divergence events within the species is not resolved (e.g., Won and Hey 2005; Becquet et al. 2007; Hey 2010). An accurate timescale of evolution of our closest relatives is fundamental to investigating a range of important questions, from the emergence of pathogens to the nature of the adaptive changes that have occurred within humans and apes. [...]
The rate of evolution in the chimpanzee-plus and bootstrapped-chimpanzee analyses were calibrated by applying lognormally distributed priors about robustly supported estimates of divergence events at three internal nodes (Raaum et al. 2005): Old World monkey–hominoid (23 Ma), orangutan–African ape (14 Ma), and chimpanzee–human (6 Ma). [...]
e used lognormal calibration distributions with lognormal means of zero and lognormal standard deviations of 0.56, and we offset these distributions by 22 Ma (Old World monkey–hominoid), 13 Ma (orangutan–African ape), and 5 Ma (chimpanzee–human). This ensured that the median values of the sampled distributions were equal to and the mean values were slightly greater than the respective 23, 14, and 6 Ma point calibrations used by Raaum et al. (2005). [...]
In this study, we performed the first mtDNA-based analysis of the timing and topology of diversification within the P. troglodytes lineage using 24 newly derived full-length chimpanzee mitochondrial genomes. By simultaneously incorporating speciation and population-level demographic parameters into our analyses, we also obtained tMRCA estimates of major primate lineages back to the most recent common ancestor preceding the split of New World monkeys from Old World monkeys and the Great Apes.
http://mbe.oxfordjournals.org/content/28/1/615.full (the study can be downloaded in pdf format via this link)
Chimpanzee mtDNA:
http://i39.tinypic.com/33445y1.jpg
Chimpanzees are our closest cousins among living animals, we diverged from them ~ 6 million years ago. Gorillas are our second closest cousins, and Orangutans the third:
http://i41.tinypic.com/2q8yiit.png
http://www.nature.com/nature/journal/v469/n7331/full/nature09687.html