AP BIOLOGY Chapter 25

LE Paranthropus robustus Homo ergaster Homo sapiens Homo neanderthalensis ? Paranthropus boisei Australopithecus africanus Kenyanthropus platyops Australopithecus garhi Australopithecus anamensis Homo habilis Homo erectus Homo rudolfensis Australopithecus afarensis Ardipithecus ramidus Orrorin tugenensis Sahelanthropus tchadensis Millions of years ago

SYSTEMATICS EXTANT SPECIESEXTINCT SPECIES

LE Deletion Insertion

LE 25-3 Rivers carry sediment to the ocean. Sedimentary rock layers containing fossils form on the ocean floor. Over time, new strata are deposited, containing fossils from each time period. As sea levels change and the seafloor is pushed upward, sedimentary rocks are exposed. Erosion reveals strata and fossils. Younger stratum with more recent fossils Older stratum with older fossils

LE 25-4 Dinosaur bones being excavated from sandstone Casts of ammonites, about 375 million years old Boy standing in a 150-million-year-old dinosaur track in Colorado Tusks of a 23,000-year-old mammoth, frozen whole in Siberian ice Petrified trees in Arizona, about 190 million years old Insects preserved whole in amber Leaf fossil, about 40 million years ago

Absolute “radiometric” dating Half-life of elementsHalf-life relative to time

Relative fossil dating using index fossils

LE North American Plate Eurasian Plate Philippine Plate Indian Plate Arabian Plate Australian Plate Antarctic Plate African Plate Scotia Plate South American Plate Nazca Plate Pacific Plate Cocos Plate Juan de Fuca Plate Caribbean Plate

LE Volcanoes and volcanic islands Trench Oceanic ridge Oceanic crust Subduction zone Seafloor spreading

LE By about 10 million years ago, Earth’s youngest major mountain range, the Himalayas, formed as a result of India’s collision with Eurasia during the Cenozoic. The continents continue to drift today. By the end of the Mesozoic, Laurasia and Gondwana separated into the present-day continents. By the mid-Mesozoic Pangaea split into northern (Laurasia) and southern (Gondwana) landmasses. At the end of the Paleozoic, all of Earth’s landmasses were joined in the supercontinent Pangaea Millions of years ago Cenozoic Mesozoic Paleozoic North America Eurasia Africa India South America Madagascar Australia Antarctica Laurasia Gondwana Pangaea

LE 26-9 NORTH AMERICA Chicxulub crater Yucatán Peninsula

Taxonomy of Life

LE 25-9 Carnivora Panthera pardus (leopard) Mephitis mephitis (striped skunk) Lutra lutra (European otter) Canis familiaris (domestic dog) Canis lupus (wolf) Species Genus Family Order FelidaeMustelidaeCanidae PantheraMephitisLutraCanis

Fig: Homologous Structures

Fig: Biogeography and Convergent Evolution

LE Hair Amniotic (shelled) egg Four walking legs Hinged jaws Vertebral column (backbone) Character table CHARACTERS TAXA Lancelet (outgroup) LampreyTunaSalamander TurtleLeopard Turtle Leopard Hair Amniotic egg Four walking legs Hinged jaws Vertebral column Salamander Tuna Lamprey Lancelet (outgroup) Cladogram

LE Drosophila Lancelet Fish Amphibian Bird Human Rat Mouse

LE 25-10a Grouping 1 Monophyletic

LE Drosophila Lancelet Fish Amphibian Bird Human Rat Mouse Cenozoic Mesozoic Paleozoic Neoproterozoic Millions of years ago

LE 25-15ab Sites in DNA sequence I Species 1 Base-change event Bases at site 1 for each species II III IV IIIIIIIV

LE 17-5 Second mRNA base First mRNA base (5 end) Third mRNA base (3 end)