Bio 1M03 - Test 2 Exam Questions & Answers Solved 100%

Angiosperms - Answer - ovules are covered by ovary - vascular plant w flowers - produce fruit - has seeds (innovative) - most diverse land plants - dominated habitats in cretaceous period Gymnosperm - Answer Ovules lack cover Relationship between Angiosperms/Animals - Answer - Coevolved (complex) - Animals assist with pollination/defense/disperal - Animals are rewarded with nect/fruit/shelter - Allows for development of niches/diversification Dating Ocean Core Strata - Answer - O16 evaporates more readily than O18 -Temperature/enviroment can be inferred from fossil record by O16:O18 in ocean cores -warm climates: more O16 in ocean - cold climate: less O16 in ocean C-14 Fossil Dating - Answer When animal dies, C-14 decayse to N-14; amount of isotope can estimate age Potassium Argon Dating - Answer Argon present in volcanic rock is due to potassium decay Other types of fossil dating - Answer 1. thermoluminescence dating 2. electron-spin resonance dating 3. uranium lead dating (have large confidence interval) Relative fossil dating methods - Answer 1. magnetic reversal 2. extinct/distinct species of animal Characteristics of Primates - Answer 1. opposable thumbs, grasping hands, prehensile tails 2. hind dominated posture 3. stereoscopic vision 4. short snouts 5. nails 6. large brains Closest Living Relative to Primates - Answer Colugo (flying lemur) from southeast asia Anthropoids - Answer common ancestor of old world and new world monkeys (each other's closest relative) Platyrrhines - Answer New World monkeys; "flat-nosed" Catarrhines - Answer Old World Monkeys, Apes, Humans; "down-ward nose" Strepsirhines - Answer Prosimians; "wet nose" Haplorrhines - Answer New world monkeys, old world monkeys, apes, tarsiers; "dry nose" Prosimians - Answer - Large olfactory lobes - Bicornuate uterus - Reflective layers in eyes - Nocturnal Tarsiers - Answer - Huge eyes - Good hearing - Long feet/fingers New World Monkeys - Answer - have prehensile tails (only ones) - Unique social system - Monogamous pair bonds - lack tricolour vision - non opposable thumbs Old world Monekys - Answer - no prehensile tails - large sexual dimorphism - non monogamous - diurnal - grasping hands/feet Middle Eocene - Answer Primates occured in North America, Europe, Asia, Africa (not South America), dispersal event across South Atlantic Dispersal of New World Monkeys - Answer - occured late oligocene - South America and Africa were closer at that time - associated with climate warming - dispersed across South Atlantic (no fossil evidence in North America) - after dispersal, diversified to new world primates Teeth - Answer - reflect dietart specialization - corresponds with natural selection (structure exploits enviroment) -use them to age primate -found often in fossil record Insectivore Teeth - Answer - sharp pointed incisors - 3 cusped triangular molars - tear open insect exoskeletons Folivore Teeth - Answer - thick enamel - shearing blade on premolar - slicing crests on molars - shred through tough leaves Frugivore Teeth - Answer - large incisors - large canines - thin enamel - parallel ridges on small molars - open tough fruit rinds Hominoids - Answer - ape, gorillas, ariganantangs, humans - different sental/skeletal traits, brain size, life history patterns - long arms/fingers, short legs - no tails Hominins - Answer human lineage after divergence from chimps/bonobos, has derived characteristics (australopithecus, paranthropus, kenyanthropus) Primate Social Systems - Answer - intelligent - complex Gibbons Social System - Answer monogamous, pair bond for life Orangutans Social System - Answer solitary, bi-maturation, occasionally force copulate Gorillas Social System - Answer harem, conduct infanticide Chimps Social System - Answer male dominated hierchy, multi male/multi female groups, preform raids to capture females Bonobos Social System - Answer female dominated hierarchy, strong female bonds, lesbians Reasons for Favouring Bipedalism - Answer 1. helps regulate temperature 2. allows hominins to carry objects/forage 3. response to increased offspring dependence How are humans different from other apes? - Answer 1. fully bipedal 2. long juvenile period 3. large brains 4. spoken language/symbolic culture 5. parabolic dental arcade, thick molar enamel, reduced canine teeth, large molars Chimp-Human Split (how'd we change) - Answer - shift 4 legs to 2 - change in spine/skull/foot structure - position of foramen magnum changes - tibia/femur alignment alters - pelvis flares/flattens - change in muscularature - MRCA 5-7 mya Ancestral Features - Answer - small molars - larger canines (relative to humans) - large brow ridge - small brain case - receeding forehead Derived Features - Answer - foramen magnum is forward (bipedalism) - small canines (relative to chimps) - flattened face Laetoli Footprints - Answer - 3.5 mya - illustrates bipedalism Phylogeny Controversy - Answer morphological info is subjective (hard to distinguish homology and homoplasy), and we do not have DNA Hunting - Answer Not uniquely hominin; sophistication however is (used tools) Early hominin behaviour - Answer - shared food - collected/hunted - divided labour - multi-male/multi-female Types of Foraging - Answer 1. Collection - plucking off trees 2. Extraction - requires effort 3. Hunting - cooperation Division of Labor - Answer done by sex/age males: hunt (peak age 30) females: extract (peak age 50), more compatible with childcare Hunting - Answer done by humans required learning - tooth marks on top of cut marks