Unit 6: Adaptations Over Time Ch 12: pages 332-353

Ideas About Evolution Millions animals __________ of species or plants, __________, and other organisms live on Earth today __________- a group of ____________ that share ________ characteristics and can ___________ among themselves to produce _______ offspring organisms similar Species reproduce fertile

Wildcats Share Do you think all the species on Earth are exactly the same as they were thousands or even millions of years ago, or do you think any of them have changed?

Ideas About Evolution Evolution characteristics ___________-changes in inherited _______________ over _______ time

Ideas About Evolution Jean Baptiste hypothesis ______ ________ de Lamarck proposed a ____________ to explain how species _________ over time His hypothesis was called the ____________ of __________ traits It states that ________ developed during a ________ organism’s lifetime are inherited by its __________ Ex: Scientists ________ this idea and found the evidence _______ support Lamarck’s hypothesis change inheritance acquired traits parent offspring Large muscles in a parent developed by hard work aren’t passed to offspring studied didn’t

Ideas About Evolution HMS Beagle South An English ship the _____ ________ set out to explore _______ America On board was young naturalist ________ ________ He was amazed by the _________ of life on the ____________ islands Darwin ______________ the animals here must have come from _________ and South America However, the islands were home to many ________ Darwin had not seen in South America Charles Darwin variety Galápagos hypothesized central species

Ideas About Evolution finches 13 Darwin observed _____ species of _________ on the Galápagos Islands They were all similar except for differences in ______ size, beak ________, and ________ habits All these finches were similar to one finch ________ seen in ________ America Darwin reasoned that these finches had to compete for _______ Finches with a beak ________ that allowed them to eat _________ food survived longer and produced more _________ Eventually these groups of ________ became separate ________ body shape eating species South food shape available offspring finches species

Ideas About Evolution After Darwin returned to England he continued to think about and study the _____________ he had made He collected more __________ on __________ traits by breeding racing _________ He also studied breeds of ______ and varieties of ________ He developed a ________ of __________ that is accepted by most scientists today observations evidence inherited pigeons dogs flowers theory evolution

Ideas About Evolution experiments inherited Many other scientists conducted _____________ on __________ characteristics based on Darwin’s _____________ After many years Darwin’s ideas became known as the theory of __________ by _________ selection _________ _________-organisms with _______ best suited to their _____________ are more likely to survive and __________ These traits are _________ to more __________ observations evolution natural traits Natural selection environment reproduce passed offspring

Ideas About Evolution population individuals A ___________ is all of the ___________ of a species living in the same ______ Members of a _______ population compete for ________ space, ______, and other __________ Those that are best able to _________ are more likely to reproduce and _______ on their traits to the next ____________ area large living food resources survive pass generation

Ideas About Evolution Principles of Natural Selection Organisms produce _______ offspring than can ________ Differences, or ___________, occur among individuals of a _________ Some variations are _________ to offspring Some variations are ________. Individuals with helpful variations ________ and reproduce better than those without these variations more survive variations species passed helpful survive

Ideas About Evolution Principles of natural selection (continued) 5. Over time, the __________ of individuals with helpful ___________ make up more of a ____________ and eventually may become a separate _________ offspring variations population species

Ideas About Evolution theory Darwin’s ________ of natural selection emphasizes the ___________ among individuals of a ________ ___________-an ___________ trait that makes an individual _________ from other members of its species Variations result from ____________ changes, or mutations, in an organism’s ________ Over time, more and more ___________ of the species might inherit these variations differences species Variations inherited different permanent genes individuals

Ideas About Evolution variations If individuals with certain __________ continue to survive and ___________ over many generations, a new species can _______ _____________- any ___________ that makes an organism better suited to its _____________ The variations that result in an ___________ can involve an organisms _______, shape, ___________, or chemical makeup _____________ is an adaptation reproduce evolve Adaptations variations environment adaptation color behavior Camouflage

Wildcats Share Infer how its coloration gives this scorpion fish a survival advantage. Infer what might happen to an albino lemur in its natural environment

Ideas About Evolution genetic Over time, the _________ makeup of a species might change its _____________ Many kinds of ______________ factors help bring about __________ When and individual of the _______ species move into or out of an area, they might _______ or remove genes and ___________ This could be compared to a family from another __________ moving into your ______________ and bringing different foods, __________ and way of speaking appearance environmental changes same bring variations country neighborhood customs

Ideas About Evolution lakes geological Sometimes _______, lakes, or other ___________ features isolate a _______number of individuals from the rest of a ____________ Over several generations, variations that _______ exist in the ________ population might begin to be more common in the _________ population ____________ can also occur causing variations to populations Over time, the two populations can become so __________ that they no longer can ________ with each other small population don’t larger isolated Mutations different breed

Ideas About Evolution agree quickly Scientists do not ________ on how _________ evolution occurs Most scientists agree that __________ supports both of these models Darwin hypothesized that __________ happens slowly ____________- the ________ that describes evolution as a _______, ongoing process by which one species __________ to a new species According to this model, a continuing series of ___________ and variations over time will ________ in a new species evidence evolution Gradualism model slow changes mutations result

Punctuated equilibrium Ideas About Evolution Punctuated equilibrium rapid ____________ ___________- this model shows that ________ evolution comes about when the mutation of a few ________ results in the ____________ of a new species over a relatively ______ period of time This could happen over a few __________ or million years _________ can change in just a few _________ genes appearance short thousand Bacteria decades

Clues About Evolution fossils Most of the evidence for evolution comes from ________, these are the __________, an imprint, or a trace of a ____________ organism Most fossils are found in _____________ rock ___________ ______- formed when ________ of sand, silt, mud, or ______ are compacted and ___________ together, or when __________ are deposited from a solution Fossils are found more often in ___________ The fossil record provides evidence that living things have evolved remains prehistoric sedimentary Sedimentary rock layers clay cemented minerals limestone

Clues About Evolution ages Two basic methods can be used to estimate the _______ of rocks and ________ One of these methods is ________ _______ which is based on the idea that in _____________ areas, __________ rock layers are deposited on top of older rock layers Provides only an ___________ of a fossil’s age The estimate is made by comparing the _______ of rock layers found ________ and below the fossil layer fossils Relative dating undisturbed younger estimate ages above

Clues About Evolution age A more accurate estimate of the ______ of a rock layer can be found by using ____________ elements __________ _________- an element that gives off a ________ amount of radiation as it slowly changes to a _______________ element Scientists can estimate the age of a rock by ____________ the amount of ____________ element with the amount of nonradioactive element in the rock radioactive Radioactive element steady nonradioactive comparing radioactive

Clues About Evolution precise This type of dating is not always _________ because the _________ amount of radioactive element in the rock can never the determined for ________ original certain

Clues About Evolution record Fossils provide a ________ of organisms that lived in the past The fossil record is _____________, or has gaps, like a _______ with missing pages The _______ exist because _______ organisms do not become fossils By looking at fossils scientists conclude that many _________ forms of life existed ________ in Earth’s history, and more _________ forms of life appeared ________ Fossils provide _________ evidence that evolution has occurred incomplete book gaps most simpler earlier complex later indirect

Clues About Evolution Scientists can use fossils to make _________ that show what organisms might have ________ like Scientists can sometimes determine whether organisms lived in _________ groups or alone, what types of _______ they ate, what kind of _____________they lived in, and many other things about them Most fossils represent _________ organisms models looked family food environment extinct

Clues About Evolution Sometime evolution can be observed _________ This is seen in ___________ resistant bacteria or pesticide resistant __________ Many examples of _________ evidence for evolution exist They include similarities in __________ structure, the chemical makeup of organisms including _______, and the way organisms develop into ________ directly penicillin insects indirect embryo DNA adults

Clues About Evolution ____________-the study of embryos and their ______________ An embryo is the __________ growth stage of an organism Embryology development earliest

Wildcats Share What do the structures shown have in common?

Clues About Evolution Although they have __________ functions, each of these structures is made up of the ________ kind of bones _____________- body parts that are similar in ________ and structure Homologous ___________ can be similar in __________ They often indicate that two or more species share a common __________ different same Homologous origin structures function ancestor

Clues About Evolution _________ _________- structures that don’t seem to have a __________ Manatees, snakes, and ________no longer have back _______, but like all animals with legs, they still have a ________ bone The human ___________ is a vestigial structure Scientist _____________ that vestigial structures are body parts that once functioned in an __________ Vestigial structures function whales legs pelvic appendix hypothesize ancestor

Clues About Evolution Scientists compare ______ from living organisms to identify ____________ among species Examinations of _________ DNA often provide additional ___________ of how some species evolved from their ________ ancestors By looking at ______ scientists also can determine how closely _________ organisms are _________ DNA also can suggest __________ ancestry DNA similarities ancient evidence extinct DNA related Similar common

The Evolution of Primates __________- a groups of ___________ including humans, monkeys and apes, that _______ characteristics such as opposable _________, binocular vision (gives ability to judge ___________), and flexible shoulders that allow their arms to ________ Primates mammals share thumbs distances rotate

The Evolution of Primates __________- humanlike primate that appeared about _______ million to six million years ago, ate both ________ and meat, and walked upright on two legs Share characteristics with _________, orangutans, and chimpanzees, but a larger _________ separate them from the apes A fossil skull was discovered in South Africa, it has a ________ space for a brain but it has a humanlike ______ and teeth Named Australopithecus was one of the oldest ___________ discovered Hominid four plants gorillas brain small jaw hominids

The Evolution of Primates Later an almost-__________ skeleton of Australopithecus was discovered in northern Africa This fossil was called _______ and had a small brain but was thought to have walked __________ complete Lucy upright

The Evolution of Primates A hominid fossil, more ________-like that Australopithecus was discovered in Africa It was named _______ _______ meaning “handy man” because simple stone _______ were found near him This fossil was _____ million to ____ million years old Based on fossil comparisons, scientists have suggested Homo habilis gave rise to _______ ________ about _____ million years ago human Homo habilis tools 1.5 2 Homo erectus 1.6

The Evolution of Primates Homo erectus had a _______ brain This hominid traveled to ______ and possibly _________ Homo habilis and Homo erectus are thought to be ___________ of humans because they has ________ brains and more human- like _________ larger Europe Asia ancestors larger features

The Evolution of Primates The _______ record indicates Homo sapiens evolved about _________ years ago ______ ________- early __________ that likely evolved from Neanderthals and Cro-Magnons fossil 400,000 Homo sapiens humans

The Evolution of Primates _____________ had short, heavy bodies, with ______ bones, small chins and _______ brow ridges ________ groups lived in _______ and used well-made ________ tools to hunt large animals They disappeared from the fossil record about ________ years ago Neanderthals thick heavy family caves stone 30,000

The Evolution of Primates _____________ fossils have been found in _________, Asia, and Australia and date from ________ to about 40,000 years in age Standing about _____ m to _____ m tall, their physical appearance was almost the same as that of _________ humans They lived in _______, made stone carvings, and _________ their dead The oldest record of _____ has been found on the walls of caves where these early humans lived Cro-Magnon are thought to be ________ ancestors of early humans Cro-Magnon Europe 10,000 1.6 1.7 modern buried caves art direct