Evidences Fossil Record and Geology
Morphology
Embryology
Biochemistry
Biogeography/ Geographical Distribution
Fossil Record Fossils
relics or impressions preserved
because the material that surrounds the organism prevents it from decaying
Mostly in sedimentary rocks
Proposed: Earth- hundreds of millions in age rather than thousand years old
Fossil Record Fossils in layers
of rocks gradual change
over time Succession is
compatible with other evidences of the major branches of descent in the tree of life
Fossil formation Cold places: animals might fell
into crevasses in ice or trapped in snow fields
Trapped in sticky sap of trees: amber
When trapped in peat bogs (certain kind of quicksand)
Otzi the Iceman is a well-preserved natural mummy of a man from about 3300 BC, found as shown in the above astonishing photographs by two German tourists, Helmut and Erika Simonby in 1991 in a glacier of the Otztal Alps in Italy, near its border with Austria. Otzi rivals the Egyptian "Ginger" as the oldest known human mummy, and has offered an unprecedented view on the habits of Chalcolithic (Copper Age) Europeans.
Mummy Juanita is a frozen Inca mummy of a teenage girl who died more than 500 years ago and was discovered in Peru in 1995 by anthropologist Johan Reinhard and his Peruvian climbing partner Miguel Zarate. Also known as Momia Juanita (original Spanish), the Ice Maiden, the Lady of Ampato and the Frozen Lady, this mummy is unfortunately going through quite a difficult modern life and not doing so well. In 2006 daily newspaper El Comercio published that an expert from the U.S. Smithsonian Institution who was vacationing in the southern Andean city of Arequipa detected dampness inside the mummy's glass-enclosed refrigeration compartment. Shown above: Mummy Juanita when found on Mount Ampato in Peru in 1995.
peat bog is a type of wetland whose soft, spongy ground is composed largely of living and decaying Sphagnum moss. Decayed, compacted moss is known as peat, which can be harvested to use for fuel or as a soil additive
PROCESS OF FOSSIL FORMATION
Sedimentary Rocks
Rain, Heat, Cold
Sand, Silt, Clay
StreamsRiversSeas
Settles down at the bottom
Of these bodies of water
Dead animals/plant
s
Are embedded into these
Sediment layers
PROBLEMS IN ASSEMBLING THE PUZZLE
Many organism die and vanish without leaving a trace
SR: only in certain bodies of water Organisms that live on mountains and
deserts* When exposed to weathering reveals fossils Fossil reconstruction
Radioactive dating Potassium 40- old fossils Carbon 14- new fossils
WHAT FOSSIL RECORDS TELL US
Represents the preserved collective history of the earth’s organisms
Shows the change followed change on earth
Morphology Similarities in Body Structure Homologous structures
meet differential needs but developed from the same body parts
different mature forms but developed from the same embryonic tissue
Vestigial Organs Reduced in size or traces of homologous organs in
other species No or little function Doesn’t affect an organism’s ability to survive and
reproduce
TRANSFORMATION TO VESTIGIAL ORGANS
new adaptations that make some organs unnecessary Serves as a clue to
an animal’s evolutionary ancestry
SIMILARITIES IN EARLY DEVELOPMENT
Shows similar genes at work Hox genes*
Occur because of the same basic control mechanism
Although organisms are different and evolved through mutations, similarities are retained**
Same groups of embryonic cells develop in the same order and in similar patterns***
“Ontogeny recapitulates phylogeny”
Ontogeny (development of an individual organism) is a replay of the evolutionary history of species (phylogeny)
Ontogeny provides clues to phylogeny
BIOCHEMISTRY Use of DNA and proteins to reflect the
relationships among speciesDNA sequences
divergencehuman vs. chimpanzee 1.2%human vs. gorilla 1.6%human vs. baboon 6.6%
DNA of all eukaryotic organism Always has the same basic structures and replicates in the
same way RNA of various species
may act little differently but are similar in structure from one species to the next
Geographic Distribution of Living Species
Species differ through their distribution
Islands have many species of plants and animals that are endemic but closely related to the nearest mainland.
• Islands with similar environmental conditions but in different parts of the world are not populated by closely related species.