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164 Cards in this Set
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Hominin
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Species belonging to our lineage (Subfamily Homininae), Which begins directly following the divergence from our last common ancestor with chimpanzees (subfamily Paninae).
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Evolution
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Change in the frequency of a gene or trait over generations (descent with modification).
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Franz Boas
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Father of modern anthropology
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Four fields of Anthropology
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• Cultural –The sum total of a group’s learned traditions. The study of human societies in a cross-cultural perspective.
• Linguistic - A study of language, it’s origin and use. • Archeology – the study of material cultures of past peoples. Prehistoric Archeologists study cultures before invention of language. Historic archeologists study after invention of language. • Biology – The study of evolution as it relates to the human species, directly or indirectly. Takes things both from humanities and from science. Sometime referred to as physical anthropology. |
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Subdisciplines of biological anthropology:
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• Osteology: the study of skeletal biology.
• Paleoanthropology: The study of the fossil record of ancestral humans and their primate relatives. • Bioarcheology: the study of human remains in an archeological context. Bioarcheologists study the effects of trauma, nutritional deficiencies, and infectious diseases on human skeletons. • Forensic anthropology: the study of human remains applied to a legal context. Forensic anthropologists focus on the identification of skeletal remains and determination of the cause of death. • Primatology: The study of living and extinct non-human primates and their anatomy, genetics, behavior, and ecology. • Human biology: the study of human growth and development, adaptation and variation, nutrition and culture, and genetics. • Molecular anthropology: The study of genetics in humans and non-human primates. |
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Typolgical Thinking
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The concept that organisms of a species conform to a specific norm. In this view variation is considered abnormal.
Origins of evolutionary thought: the Greeks: Plato and Aristotle’ essentialism. • Attempt at understanding and ordering the natural world. • The eidos (idea or type) is the only thing that is fixed and real • Observed variation is no more real than shadows on a cave wall • Gaps in nature are real – represent discontinuities between types • Immutability of species: an unalterable fixity of essence Belief is that all rabbits are different but these differences are flaws |
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The Great Chain of Being
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• Life arranged in orderly, hierarchical ladder
• Humans on top. • Groups ranked according to elements – land mammals, air (birds), water (fish) • Primate: chief bishop, or archbishop, 13th c.. PRIMATE, in this time period, meant the greatest of the species. o Lions as the best primate o Eagles as the bird primate o Whales as the fish primate o Humans as the ultimate primate • Primates: members of the order primates, 18th century. |
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Carl Linnaeus (1707- 1778) and systema Naturae
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o Botanist, inventor of modern biological classification
o Introduced the order primates- the animal primate o First time humans are included in mammalian order o Humans in Hominidae; great apes in pongidae o Binominal nomenclature: genus and species |
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Systematics: Taxonomy and Phylogeny
Terminology |
o Systematics: the study of patterns in biology
o Phenetics o Cladistics |
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Systematics: the study of patterns in biology
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o Taxonomy: biological classification. Kingdom, phylum, class, order, family, genus, spcies.
o Taxon: a group of organisms assigned to particular category. o Phylogeny: A hypothesis of evolutionary relationships. o Taxonomy works better when it reflects phylogeny. |
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Phenetics
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an attempt to classify organisms based on overall similarity, usually in morphology or other observable traits, regardless of their phylogeny or evolutionary relation.
“numeral taxonomy” o Summing similarities between taxa o Results in dendrogram o Ignores relatedness o Does not distinguish between shared and primitive traits |
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Cladistics
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an approach to classification in which items are grouped together based on whether or not they have one or more shared unique characteristics that come from the group's common ancestor and are not present in more distant ancestors.
o Phylogenetic systematics o Parsimony: the hypothesis with the fewest number of changes o Uses ancestral (Plesiomorphy) and derived (apomorphy) traits |
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Sympleplesiomorphy
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shared primitive trait: breathing with gills
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Synapomorphy
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shared derived trait: hair for mammals
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Autapomorphy
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a uniquely derived trait specific to one taxon: feathers for birds
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Clade
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A group of organisms including an ancestor and all descendants
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Paraphyletic group
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Excludes one or more descendant. If we talk about apes but don’t mean humans.
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Polyphyletic group
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Excludes the common ancestor
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Georges-Louis Leclerc, Comte de Buffon (1707-1788)
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o Relatives in different climates look different, they have biological differences.
o No framework for mechanism of change o American degeneracy- belief that people and animals in America were not as biologically superior as creatures in Europe. Buffon was finally convinced that people and animals were okay upon seeing a moose. |
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Symplesiomorprhy
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Shared primitive traits.
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Synapomorphy
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shared derived trait
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Autapomorphy
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unique derived trait
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Erasmus Darwin
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wrote Zoonomia in 1774
He translated Linnaeus into English Had early ideas about evolution. |
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Georges Cuvier (1769-1832)
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Father of comparative anatomy
• Function determines form; animals are suited for their environments • Principal of correlation of parts: organisms as integrated wholes • Modification would impair functional integrity; no evolution • Similarities between organisms result from shared functions • Tried to argue that African elephants and Asian elephants are too vey different organisms. Did not believe in evolution. • Extinction as evidence for catastrophic disasters that wiped out past life forms; new creations/migrations replace them. Catastrophism. He believed that any similarities in organisms was a result of shared functions, in similar environments. |
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James Hutton (1726-1797) and Charles Lyell (1797-1875)
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Uniformitarianism: the geological processes are uniform over time; slow gradual changes suggest ancient age of earth
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Geoffroy Saint Hilaire (1772-1844)
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• Strong advocate of evolution, publically debated Cuvier
• Presaged many evolutionary concepts: unity of composition (homology), evolutionary accidents (mutations) • Body plans and hopeful monsters • Believed that a large evolutionary accident had to occur to create a turtle. • Unity of body plans: vertebrates as inverted hopeful monsters- looked at difference between vertebrets and invertebrates. Believed that an invertebrate was born as vertebrate and propagated. These ideas are still thought about today even if largely disagreed with. |
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Homology
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• Similarity of traits resulting from shared ancestry.
• Symplesiomorphies and synapomorphies are homologies o The structure of interest evolved in a common ancestor. |
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Homoplasy
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Shared traits resulting from convergent evolution.
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Polyphyly indicates homoplasy
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• Appearnce of similar traits due to similar use, not common ancestry
• Convergent evolution (convergence), parallel evolution (parallelism) • Traits that evolve independently are called homoplasies or analogies |
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Karl Enst von Baer (1792-1876)
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• Primary germ layers: all organisms are made from same tissues
• Von baer’s law: development proceeds from general to specific. |
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Ernst Haeckel (1834-1919)
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• Ontogeny recapulates phylogeny: individual development retraces the evolutionary history of a species
• Ontogeny: growth and development. We now know he was wrong. Ontogeny does not recapitulate phylogeny • Development proceeds from general to specific! In womb. • Limb buuds: arms, legs, flippers, fins, wings vestigial limbs • Tails (human embryos possess tails, which regress to the coccyx) • Pharyngeal arches are shared developmental plan in vertebrates o Become gills and jaws in fish. But many structures in mammals: maxilla, mandible, inner ear boanes, hyoid bone, throat cartilages |
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Embryology
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• Development proceeds from general to specific within species too – e.g. , sexes. The two structures of genitals are the same 6-8 weeks in womb.
• Sexual dimorphism: differences between sexes • Genital homology |
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What has been established?
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• Orgainsms are adapted to environment
• Uniformitarianism and ancient age of earth • Organisms share a common pattern of development • Homology in comparative anatomy and embryology • Descent with modification |
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Jean Baptiste Lamarck (1744-1829) and acquired characteristics
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• Organisms are adapted to their environments
• Evolutionary change in an individuals lifetime through use or disuse • Inheritance of acquired characteristics |
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Charles Darwin (1809-1882)
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• “Gentleman amateur naturalist” on the journey HMS Beagle
• 5 year trip around the world (1831-1836)[NYU founded in 1831] • discovored and examined fossil mammals in South America • Darwin looked at Giant tortoises in the Galapagos o Dome shaped shells on lush islands o Saddle shaped on arid islands • Finches: each island hosted different finches Biogeography: the distribution of plants and animals on earth o Islands often hold endemic species( those found nowhere else) o Galapagos finch: Short beak adapted for eating seeds buried in soil o Tree finch: parrot shaped beak for stripping bark to find insects |
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Adaptive radiation
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rapid evolutionary radiation. It is an increase in the number and diversity of species in each lineage. It produces more new species, and those species live in a wider range of habitats.
Diversification from one founding species into many species occupying different area |
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Artificial Selection
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The process by which humans select which members of a species reproduce.
o Farmers select for certain features in plants (seeds, stems, leaves, fruit) o Animal breeders select for woolier coats, milk or meat production. |
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Natural selection
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the process by which certain traits enable an organism to survive and reproduce in an environment, thus increasing the frequency of those traits in future generations
o Differential reproductive success over generations o In artificial selection, The breeder chooses certain traits, whereas in natural selection, the environment molds each generations |
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Alfred Russell Wallace (1823-1913)
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• Wallace’s studies in the amazon and Malay Archipelago
• Darwin and Wallace jointly publish paper in 1858 • Darwin publishes On the Origin of Species by Means of Natural Selection in 1859 |
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Natural Selection is not just survival of the fittest
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• Evolution is about fitness: a measure of reproductive success
• Evolution by natural selection = differential survival and reproduction |
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In order for evolution by Natural selection to occur:
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• The environment must cause differential survival before reproduction
• There must be a variation between individuals and population • Trait must be heritable |
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Preformationism
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• Homunculus: a tiny version of a fully formed individual
• Problems:1) infinite homunculi, 2) hybrid domestic animals • Eventually replaced by the concept of epigenesist: an organism develops from a fertilized eggs. |
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Darwin’s blending inheritance: uniform blend of parents’ phenotypes are passed on to offspring
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• Problem: fitness effects of one parent would be blended out by the other parent; this diminishes continues with the offspring
• Variation cannot be maintained this way |
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Prokaryotic Cells
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single celled organisms such as bacteria or archea- no nucleus, so genetic material is not separate from rest of cell
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Eukaryotic Cells
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a cell that posseses a well-organized nucleus; eukaryotic organization may have facilitated the origin of multicellularity
• is surrounded by a cell membrane • Nucleus surrounded by plasma membrane: contains nuclear DNA • Cytoplasm: gel like substance that contain cells organelles |
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Organelles
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• Mitochondria produce energy through metabolic process (use oxygen to convert sugars to energy) Contain their own DNA. (mitochondria is inherited by mother.
• Endoplasmic reticulum: sites where genetic info is translated to protiens; contain ribosomes, which contain RNA molecules |
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Somatic cells
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body cells(kidney, brain, hair, etc) contain full set of paired chromosomes
o Stem cells are undifferentiated body cells in developing embryo |
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Gametes
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sex cells (ova and sperm); unpaired chromosomes (haploid-23 chromosomes)
o Zygote: fertilized egg (diploid-46 chromosomes) |
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Chromosome
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coiled strand of condensed DNA
• All somatic cells have same number of chromosomes, which consist throughout species (46 in humans, 48 in chimps and Gorillas • Each cell contains two pairs of each chromosome, one from each parent |
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Structure of DNA was first described in 1953
Deoxyribonucleic Acid |
• Doublestranded; each strand contains nucleotides
• Nucleotides: phosphate, deoxyribose sugar, nitrogen base • Bases:p purines (adenine, guanine) and pyrimidines (thymine, cytosine) • Bases held together by hydrogen bonds • A-T, G-C |
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Genetic Code: Codons contain info for synthetic protiens
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• Triplet of bases codes for an amino acid
• An amino acid chain (polypeptide) creates a protein: o Structural proteins (collagen, Keratin) o Enzymes (hemoglobin, lactose) o Hormones o Antibodies • Gene: a sequence of DNA that carries the information for synthesizing protein |
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Replication
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• Occurs during cell division
• Enzymes separate bonds- DNA unzipped • Assembly of complementary nucleotides • 1 parent DNA strand becomes two daughter strands |
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Protein synthesis
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the assembly of proteins from amino acids, which occurs at the ribosomes in the cytoplasm via mRNA
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Transcription:
In the nucleus |
1. DNA “unzips”
2. Single strand of RNA (ribonucleic acid; uracil instead of Thymine) forms and copies DNA 3. mRNA leaves nucleus and travels to ribosom 4. At the ribosome, codons are translatedto aa sequence 5. mRNA binds to ribo 6. Ribosome reads each codon one-by-one 7. tRNA brings coded for aa for each codon. Protein chain is formed |
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The genetic code is:
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• Based on triplets
• Redundant • Continuous • Universal |
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Genome:
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the sum total of all genes in an individual
• DNA: double stranded molecule that contains genetic information • Chromosome: coiled strands of condensed DNA • Gene: sequence of DNA on a chromosome that codes for protein |
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Mitosis
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somatic cell division that results in the formation of two identical daughter cells; 1 diploid becomes 2 diploid cells.
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Meiosis
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sex cell division that occurs in the testes and ovaries result in genetically distinct gametes. Results in 4 genetically distinct, haploid gametes
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Polar bodies
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discarded side products of oggenesis
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Zygote
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and ovum fertilized by a sperm.
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Nondisjunction error
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failure of chromatids to separate properly during either mitosis and meiosis
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Monosomy
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occurs when one chromosome in a pair is absent
o Turner’s syndrome |
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Trisomy
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occurs when there is an extra chromosome
o Trisomy 21 (down syndrome) o Kleinfelter’s syndrome |
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Darwin Day
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February 12
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Locus
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location of a gene on a chromosome
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Allele
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variant form of a gene
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Homozygous
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having the same allele at both loci of a gene
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Heterozygous
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having two different alleles at the loci of a gene
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George Mendel (1812-1884) “Father of Genetics”
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• Experiments on garden peas
• Demonstrated particular inheritance: the concept of heredity based on transmission of genes, or “factors” • “Rediscovered” in 1900 by William Bateson – “Genetics” ~ came up with term • Common garden pea- dichotomous variation, independent traits • Based true- produced strains of plants that resembled their parents generation after generation … homozygotes |
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Mendel’s law of segregation
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the two alleles of a gene found on each pair of chromosomes segregate into gametes
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Genetics
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• Dominant : an allele that is always expressed if present
• Recessive: an Allele that is masked when a dominant Allele is present • Genotype: genetic makeup • Phenotype: physical expression |
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Mendels second law of independent assortment:
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Traits from different genes sort independently
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Hardy-Weinberg Equlibrium:
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Null hypothesis: no evolution
No change in allele frequencies |
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Hardy-Weinberg Equlibrium Conditions
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– Diploid – must be two copies
– Sexual reproduction – Non-overlapping generations – Random mating – Large (infinite) population size – Four forces of evolution • No gene flow • No Gene drift • No mutation • No natural selection |
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Four forces of evolution: factors that cause changes in gene frequencies over generations; violate HWE
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1) Mutation
2) Gene flow 3) Natural selection 4) Genetic drift |
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Mutation:
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errors in the replication of DNA that result in random alterations in the DNA sequence
– Mutations in non-coding regions are neutral – Mutations in coding regions can be neutral or good/bad – Mutation in gametes can be passed on – The ultimate source of novel genetic variation! NO MUTATION = NO VARIATION = NO EVOLUTION |
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Gene flow:
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exchange of genetic material between populations (admixture)
– Migration with reproduction – Increases genetic relatedness between populations – Introduces new genotypes and phenotypes to populations |
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Genetic drift:
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random changes in gene frequencies in a population
– Effect inversely proportional to population size: strongest in small populations (coin flip example) – if you got heads 8/8 times… odd but not crazy. 8000/800 would be nuts! Would show random sampling can produce random outcomes. – Effect often greater over longer time periods – Random: no directionality – Fixation or disappearance of alleles |
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Bottleneck:
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dramatic reduction in the size of a population
– Results in reduced genetic variation – Long, slow process of mutation accumulation to rebuilt genetic diversity – Threat of disease (anti-disease resistance) |
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Founder Effect:
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new populations that become isolated from their parent population carry a subset of genetic variation
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Evolutionary Synthesis
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Darwin’s theory of evolution
+ Mendel’s theory of inheritance = Evolutionary synthesis |
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Forces of evolution:
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– Mutation: errors in DNA replication
– Gene flow: migration with reproduction – Genetic drift: random sampling of alleles – Natural selection: differential survival and reproduction |
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Genetic drift and natural selection
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– Drift is strongest in small populations over long time periods
– Selection can be strong in large populations over short time periods |
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Adaptation:
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evolved phenotypic traits that increase an organism’s reproductive success
– Traits that have evolved via natural selection – Strict definition: a trait that has evolved for a purpose that it is currently serving; a trait that evolved for a purpose other than its current purpose is not an adaptation |
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Adaptationism:
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all aspects of an organism have been molded by natural selection and are best understood in that context
– The Spandrels of San Marco and the Panglossian paradigm – Ignore non-adaptive means by which organisms can evolve (e.g., genetic drift, byproducts, “constraints” on evolution) |
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Types of selection
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• Natural selection acts on the phenotype, not the genotype (genotype affected through natural selection action on the phenotype)
• Directional selection: selection against one extreme • Stabilizing selection: selection against both extremes • Disruptive selection: selection for both extremes (example: study on house sparrows after a storm. The smallest froze to death, the largest couldn’t find enough food. |
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Sexual selection:
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differential reproductive success among members of the same sex in a species; non-random mating
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Reproductive potential
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Possible output of offspring by one sex
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Reproductive variance
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variation in reproductive potential in one sex compared to the other
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The sex with the more limited reproductive potential (usually females) should be competed over by the sex with the greater reproductive potential (usually males)
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– Bateman’s principle
– Limiting sex: low variance, low potential – Non-limiting sex: high variance, high potential |
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Sexual dimorphism
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Phenotypic differences between sexes
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Intrasexual selection
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competition between members of the same sex (e.g., male-male competition)
• Weaponry • Body Size • Sperm Competition |
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Intersexual selection
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mate choice (e.g., female choice)
• Direct benefits: • Protection from predators • Access to food (territory) • Help with offspring (parenting) |
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Intersexual selection
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mate choice (e.g., female choice)
• Indirect benefits (genetic quality): – Handicap principle: costly signaling – the peacock survives “in spite” of its tail – Coloration – Elaborate displays |
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Intersexual selection
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mate choice (e.g., female choice)
• Direct benefits: • Protection from predators • Access to food (territory) • Help with offspring (parenting) |
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Intersexual selection
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mate choice (e.g., female choice)
• Indirect benefits (genetic quality): – Handicap principle: costly signaling – the peacock survives “in spite” of its tail – Coloration – Elaborate displays |
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Species:
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a group of related organisms that can interbreed and produce fertile, viable offspring
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Speciation:
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formation of one or more new species
Occurs via reproductive isolation: any mechanism that prevents two populations from exchanging genetic material |
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Allopatric speciation
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Speciation occurring via geographic isolation
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Parapatric speciation
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– Speciation occurring in a continuous population
– Ring species, hybrid zones |
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Sympatric speciation
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– Speciation occurring in the same geographic area
– More common in plants than animals – Can result from disruptive selection |
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Reproductive isolating mechanisms
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any factor – behavioral, ecological, or anatomical – that prevents hybridization
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Pre-zygotic isolation:
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barriers to fertilization
– Mate recognition – Mechanical issues |
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Post-zygotic isolation
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– Sterility
– Offspring non-viability |
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Species concepts:
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How do we identify species, living and extinct?
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Biological species concept (BSC)
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• “Groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups” –Mayr
• Does not apply to the vast majority of life – bacteria, archaea, many plants and fungi, and some animals are asexual • Hybridization and ring species • Fossil record |
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Phyletic gradualism
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– Slow, incremental evolutionary change
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Punctuated equilibrium
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– Evolution by rapid bursts of change, followed by long periods of stasis
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Microevolution
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Small-scale evolution, such as changes in allele frequency, that occurs from one generation to the next
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Macroevolution
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– large-scale evolution, such as speciation events, that occurs over many generations
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Anagenesis:
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one species evolves into another over time
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Cladogenesis:
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speciation through branching of lineages
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Reproductive isolating mechanisms:
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any factor – behavioral, ecological, or anatomical – that prevents hybridization
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Pre-zygotic isolation:
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barriers to fertilization
– Mate recognition – Mechanical issues |
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Post-zygotic isolation
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– Sterility
– Offspring non-viability |
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Species concepts
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– How do we identify species, living and extinct?
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Biological species concept (BSC)
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– “Groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups” –Mayr
– Does not apply to the vast majority of life – bacteria, archaea, many plants and fungi, and some animals are asexual – Hybridization and ring species – Fossil record |
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Modern Evolutionary Synthesis
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– Incorporation of paleontology
– Micro- vs. macroevolution – Tempo and mode of speciation • Anagenesis: one species evolves into another over time • Cladogenesis: speciation through branching of lineages • Phyletic gradualism • Slow, incremental evolutionary change • Punctuated equilibrium • Evolution by rapid bursts of change, followed by long periods of stasis |
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Microevolution
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Small-scale evolution, such as changes in allele frequency, that occurs from one generation to the next
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Macroevolution
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• large-scale evolution, such as speciation events, that occurs over many generations
Macroevolution as an extension of microevolution: macroevolution occurs through the conversion of within-species variation into between-species variation |
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Adaptation:
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evolved phenotypic traits that increase an organism’s reproductive success
– Traits that have evolved via natural selection – Strict definition: a trait that has evolved for a purpose that it is currently serving; a trait that evolved for a purpose other than its current purpose is not an adaptation |
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Adaptationism:
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all aspects of an organism have been molded by natural selection and are best understood in that context
– The Spandrels of San Marco and the Panglossian paradigm – Ignore non-adaptive means by which organisms can evolve (e.g., genetic drift, byproducts, “constraints” on evolution) |
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Hemophilia:
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absence of clotting factor – hemorrhage, joint damage
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X-linked disorders
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mutations to genes on the X chromosome
– Disorders appear to skip a generation – Only males afflicted… or very rarely females – Males only have 1 copy of X; not passed on to sons – Females carriers can produce hemophiliac sons |
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Codominance
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alleles are co-expressed; neither is dominant
– ABO blood system |
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Cline:
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continuous gradation from one geographic region to another
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Johann Friedrich Blumenbach (1752-1840)
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“Father of physical anthropology”
• Races “impossible to separate… by any but very arbitrary limits.” • Nonetheless… 5 races for the sake of convenience: • Ethiopian • American • Asian • Caucasian • Malayan • Refuted Linnaeus’s wild men and monsters |
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Samuel George Morton (1799-1851)
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Crania Americana – innate differences in cranial size and brain capacity among races
• Polygenism: separate origins of humans – races were created separately or evolved from separate ancestors • 6,000 years is not enough time to account for five races • Polygenism becomes widespread in the 19th century • Monogenism: single origin of humans – creation, then common ancestry |
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Skin Color
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• Function of skin
– Thermoregulation: maintaining body temperature – Metabolism of vitamins – Protection from physical/chemical injury and microorganisms • 95% keratinocytes: regular skin cells; synthesized deep and migrate to the surface • 5% melanocytes: pigment cells |
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What is a mammal?
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• Chordate (Chordata): animal with a notochord
• Craniate (Craniata): chordate with a skull • Vertebrate (Vertebrata): craniate with a spinal column • Gnathostome (Gnathostomata): vertebrate with a jaw • Tetrapod (Tetrapoda): gnathostome with four limbs – amphibians, reptiles (incl. birds), mammals • Amniote (Amniota): tetrapod with amniotic egg/membrane • Mammal (Mammalia): amniote with mammary glands & hair |
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Mammal characteristics
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– Mammary glands
– Hair – Homeothermy (warm-bloodedness) – Limbs under the body – Heterodonty • differentiation of teeth |
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Mammalia
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– Prototheria (monotremes) - means before beast. Ie Platypuses and echidnas.
– Theria – means beast. • Metatheria (marsupials) – kangaroos . Marsupium means pouch • Eutheria (placentals) – means true bests – humans included here |
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Afrotheria
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Mostly live in Africa. Elephants, hyraxes, dugongs, elephant shrews.
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Xenarthra
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Mostly South American Central mammals. Anteaters, armadillos, sloths.
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Laurasiatheria
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From Eurasia. Very diverse group. Lions, Bats, whales, warthogs, bears, horse, rhinos. All domesticated animals.
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Euarchontoglires
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Primates used to be classified in a group called Archonta, same category as flying lemurs and many shrew like creatures. Now we consider Primates as Euarchonta. Euarchontoglires also include rodents and rabbits. Probably the closest living relative of primates are colugos (flying lenurs.
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Order of Primates and two suborders
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Strepsirhines (wet nose) – includes Lemurs and Lorris
Haplorhines – Tarsiers, New World Monkeys, Old world monksys |
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Strepsirhines (wet nose)
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includes Lemurs and Lorris
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Haplorhines
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Tarsiers, New World Monkeys, Old world monksys
• 2 infraorders • Tarsiiformes • Anthropoidea (Simiiformes) |
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Strepsirhines 2 major subdivisions
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Lemuriformes (lemurs): Madagascar …… and Lorisiformes (lorises and galagos)
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Lemuriforms
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Lemurs are only in Madagascar
Nocturnal and diurnal Small to medium size 1-2 ounces à 20 lbs Solitary to large social groups Variety of foods Insects Exudates Fruit Leaves |
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Lorisforms
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• Lorises (Lorisidae) and galagos (Galagidae)
• Africa and Asia • Lorisidae Nocturnal Slow, “cryptic” movement Relatively small body size Solitary Insects Exudates Flowers Fruits |
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Galagidae
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• “Bushbabies”
• Nocturnal • Strong leapers • Solitary • Fruit • Insects • Exudates |
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Tarsiiforms
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• Tarsiers
• Mix of primitive and derived features • Nocturnal • Very strong leapers • Solitary -- Monogamy • Faunivory • Island SE Asia |
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Anthropoidea
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• 2 parvorders
o Platyrrhini (NW monkeys) o Catarrhini (OW monkeys) |
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Catarrhini
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Catarrhines
Old World monkeys and apes Large-bodied More terrestrial Fruits and leaves • 2 superfamilies: – Cercopithecoidea (OWM) – Hominoidea (Apes and humans) |
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Cercopithecoidea
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Old World monkeys
Widespread across Africa and South Asia Large social groups 1 Family: Cercopithecidae 2 Subfamilies: Cercopithecinae Colobinae |
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Cercopithecinae
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Arboreal and terrestrial quadrupeds
Mostly Africa Mostly fruit Cheek pouches Guenons and relatives |
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Macaques
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Wide distribution
Mangabeys Africa Paraphyletic |
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Drills and mandrills
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Large body size
High sexual dimorphism Africa |
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Baboons
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Large body size
High sexual dimorphism Widespread across Africa |
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Colobinae
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Leaf eating monkeys (colobines)
Complex stomqchs Africa- Colobus Monkeys Asia (langurs, odd-nosed monkeys) |
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Hominoidea
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1. Apes
2. Africa and Asia 3. Wide Range of Social Systems • Multi-male, multi female groups (chimpanzees, bonobos) • One Male (harems) (Gorillas) • Solitary (orangutans) • Monogamous (gibbons) • Any or all of above (humans) 4. Fruits and leaves |
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Hominoidea
Five genera in two families: |
• Hylobatidae
– Hylobates (gibbons) • Hominidae – Pongo (orangutans) – Gorilla (gorillas) – Pan (chimps, bonobos) – Homo (humans) |
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Hylobatidae
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Gibbons, or lesser apes – range from 8 to 20 lb
SE Asia Ripe fruit specialists Brachiation Monogamy. Males and females are sometimes sexually dichromatic (in other words… in Gibbon’s case, males and females are different colours.) |
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Hominidae
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Hominids, or great apes
Africa and SE Asia Two subfamilies: Ponginae (orangutans) Homininae (African apes, including humans) |
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Ponginae
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• Orangutans
– 2 populations (species or subspecies) – Borneo – Sumatra – Largest arboreal mammal – When terrestrial, which is rare in the wild and mainly restricted to large males, fist-walking (sides of hands) – Highly sexually dimorphic – females ~ 60 kg, males ~ 120 kg – Characterized by male bimaturation: small vs. full adult morph. This is largely about dominance and hormones. Dominant males become larger. – Very long forelimbs and hook-like hands with short thumbs – Diet: fruit, leaves, shoots, bark |
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Gorillas
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– 2 species
– Gorilla gorilla (western lowland gorillas) – Gorilla beringei (eastern gorillas) – Largest living primate – Extreme sexual dimorphism • females ~ 80 kg, males ~ 175 kg – Folivorous diet – Lowland gorillas are more arboreal and frugivorous than mountain gorillas – presence of fruit-bearing trees! – Mountain gorillas second most terrestrial primate – Knuckle-walking on the ground, climbing and suspension in the trees |
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Chimpanzees and bonobos
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– Pan troglodytes (common chimpanzee)
– Pan paniscus (bonobo, or “pygmy” chimpanzee) – Several subspecies across sub-Saharan Africa – Primarily fruits and nuts; also leaves, honey, insects, and meat – Habitats range from rainforest to woodlands to dry savannahs – Knuckle-walking, climbing, and suspension |
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Primate Characteristics
Symplesiomorphies (primitive; ancestral) |
• Pentadactyly (5 digits)
• Two lower arm bones (radius & ulna) • Clavicle – bony bridge to the shoulder • Generalized body plan |
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Primate Characteristics
Synapomorphies (derived traits) |
• Reduced olfaction
– Shorter snouts, fewer whiskers, smaller olfactory bulb • Emphasis on vision – Forward-facing eyes (stereoscopic vision) • Reduced olfaction – Shorter snouts, fewer whiskers, smaller olfactory bulb • Emphasis on vision – Forward-facing eyes (stereoscopic vision) – Post-orbital bar or closure • Tendency for vertical posture • Grasping hands and feet • Nails (vs. claws) • 1st digit opposability • Petrosal bulla (inner ear bones housed in petrosal portion of temporal bone) • Increased flexion to skull base • Tendency for large brains • Slow life history • Fewer young • More parental investment • Longer developmental period • Later reproduction • Longer lifespan |
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Post-orbital bar/closure
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• Post-orbital bar in strepserhines
• Partial closure in tarsiers • Full closure in anthropoids |
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Strepsirhine-Haplorhine differences
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• Rhinarium in streps; separate nose/mouth in haps
• Unfused frontal and mandible in streps • Tapetum lucidem (eye shine) in streps • Haps lack tapetum lucidem • Nocturnal haps have big eyes • Retention of claw on 2nd digit in streps – grooming/toilet claw • Tooth comb (projecting incisors and canine) as derived in streps • Tarsiers are haps that retain grooming claws and unfused mandibles • Orbit is partially closed in tarsiers • Frontal bones are fused • Broad, laterally-facing nostrils in plats; narrow and down in cats • Plats retain 3 premolars; cats have just 2 premolars • Dental formula (1/4 of the mouth): 2 incisors, 1 canine, 3 premolars, 3 molars (2.1.3.3) 2.1.2.3 in cats |
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Cercopithecoid-Hominoid differences
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• Cercos have bilophodont molars
– Crests between cusps • Apes have bunodont molars – Rounded cusps – Y-5 cusp pattern • Cercos possess tails • Apes lack tails (coccyx) • Long arms, extensive shoulder mobility in apes • Upright trunk posture in apes – Dorsally-located scapulae – Wide rather than deep chest • Shorter, less flexible lower back in apes – Fewer and shorter lumbar vertebrae |
