| A | B |
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| * Evolution above the species level (ie - the kind that creates new species) is called _______. | macroevolution p459 |
| ** A(n) ______ is a structure that originally evolved for a different purpose than the one it has presently. | exaptation (ex: Feathers probably evolved for insulation and were later modified to help with flight) p477 |
| ** _____ is an evolutionary change in the rate or timing of developmental events and can have a significant impact on body shape. | Heterochrony (In the human evolutionary lineage, mutations that slowed the growth of the jaw relative to other parts of the skull produced an adult whose head resembles that of a chimpanzee infant) p473,  |
| ** In ______, the rate of reproductive development accelerates compared to somatic development, leading to sexually mature species that retain body features that were juvenile structures in an ancestral species. | paedomorphosis (This adult aquatic salamander that retains the gills common to all juvenile amphibians is a classic example) p474,  |
| * ____ genes determine such basic features as where a pair of wings and a pair of legs will develop on a bird or how a flower’s parts are arranged. | Homeotic genes p474 |
| * The products of one class of homeotic genes called ____ genes provide positional information in animal embryos. | Hox (Examples include the development of fins in fish and limbs in tetrapods) p474 |
| ** According to the ________________ model, trends may result when species with certain characteristics endure longer and speciate more often than those with other characteristics. | species selection model (Although this is considered detailed knowledge as far as the terminology is concerned, it is fundamental as far as a concept goes. Go back and read page 479, the last of this chapter. It's fascinating!) p479 |
| ** _____ is a method paleontologists use for determining the ages of rocks and fossils on a scale of absolute time, based on the half-life of radioactive isotopes. | Radiometric dating p461,  |
| * The number of years it takes for 50% of an original sample of a radioactive isotope to decay is called the isotope's _____. | half-life p461, |
| ** Fossilized bacterial mats that formed as far back as 3.5 billion years ago are called _____. | stromatolites p462 |
| ** The most recent supercontinent that was formed near the end of the Paleozoic era (250 million years ago) when plate movements brought all the landmasses of Earth together was called ______. | Pangaea (Supercontinents also formed 2 other times within the last billion years, once around a billion years ago and another time around 600 million years ago) p466,  |
| ** The half-life of carbon-14 is 5730 years. If there was 10 milligrams of carbon-14 in a bone fragment 11,460 years ago, how much carbon-14 would still be left today? | 2.5 grams (After 5730 years, half of the 10 gram original sample would be left, so after 5730 years there would be 5 milligrams. In the next 5730 years, half of that 5 grams would be left, so after a total of 11,460 years, only 2.5 milligrams would be left) p461, |
| * Scientific data indicates that Earth formed about _____ years ago. | 4.6 billion p462 |
| ** ______ are similar fossils found in the same rock strata in different locations. They allow strata at one location to be correlated with strata at another location. | Index fossils (Not in this version of the textbook, but I want you to know this term),  |
| * Each era is a distinct age in the history of Earth and its life, with boundaries marked by ________ seen in the fossil record. | mass extinctions p462 |
| ** The geologic record is divided into three _____. These are further subdivided into _____ which themselves are further subdivided into ____. | Eons, eras, periods p461,  |
| * The earliest known fossils date back about _____ years ago. | 3.5 billion p462 |
| ** Prokaryotes were the only life forms from at least _____ to ______ years ago. | 3.5 billion to 1.8 billion (Eukaryotes originated about 1.8 billion years ago) p514 |
| ** Oxygen releasing photosynthetic bacteria are called ____. | cyanobacteria (also known as blue-green bacteria) p463 |
| * Earth's early atmosphere was much different than today's atmosphere in that it lacked _____. | oxygen p462 (The book no longer makes this explicit, but it's true and important) |
| ** The oldest fossils of eukaryotic organisms date back about _____ years ago. | 1.8 billion p463 |
| ** Multicellular eukaryotic organisms first appeared about ___ years ago. | 1.3 billion p463,  |
| * What type of rocks are most fossils in? | sedimentary p460 |
| ** The different layers in sedimentary rock are called ____. | strata p460 |
| ** The early, gradual rise in atmospheric oxygen levels was probably brought about by ancient ______. | cyanobacteria p463 |
| * The _____ refers to a relatively brief period of time in geologic history when many present-day phyla of animals first appeared in the fossil record. This burst of evolutionary change occurred about 535 to 525 million years ago and saw the emergence of the first large, hard-bodied animals. | Cambrian Explosion p463 |
| ** The Cambrian explosion refers to a relatively brief period of time in geologic history when many present-day phyla of animals first appeared in the fossil record. This burst of evolutionary change occurred about _____ to ______ years ago and saw the emergence of the first large, hard-bodied animals. | 535 to 525 million years ago p463 |
| * What caused the major mass extinctions at the end of each era? | DUH!!! (Actually, some scientists, now dead, believed that the extinctions were caused by disruptive global environmental changes, but Chuck took issue with this) p521,  |
| ** According to the theory of __________, the continents essentially float on the hot underlying portion of the mantle. The continents can move relative to each other in a process called "continental ____." | Plate tectonics, continental drift p466 |
| * How long ago did dinosaurs go extinct? | 66 million years ago p469 |
| * Evolutionary change often occurs due to adaptations to a _______. | changing environment p471 |
| ** According to the ________________ model, species can be looked at like the life of a human. A birth with sudden quick change, a life span that often spawns other species, like humans spawn children, then a death analogous to extinction. The species that spawns the most other highly successful species before it's eventual extinction gets to dominate the course of history well into the future. | species selection model p479 |
| * Carbon -14 is a radioactive isotope of carbon that has a half-life of 5,730 years. The amount of carbon-14 in the atmosphere is a small but stable percentage. It is formed by the bombardment of nitrogen in the atmosphere by cosmic particles coming from the sun. When plants photosynthesize, they incorporate carbon as CO2. The percentage of radioactive carbon-14 incorporated into plant tissues is the same as the relative abundance of carbon-14 in the atmosphere. That carbon is then passed up the food chain, so that all living organisms have the same relative abundance of carbon-14 in their tissues. However, after an organism dies, the carbon-14 slowly changes back into nitrogen-14 (a stable non-radioactive isotope of nitrogen). Let's say that and human dies. What percentage of carbon of the original carbon-14 will still be in it's bones after 5,730 years? After 11,460 years? | 50%, 25% (Remember, from 5730 years until 11,460 years after the human dies, you will go from having half the original amount of carbon-14 to having half of THAT. So half of 50% is 25%) p461 |
| * TRUE or FALSE: Scientists would use carbon-14 to date fossils that are thought to be several million years old. | FALSE: (Since the half-life of of carbon-14 is only 5730 years, there would be practically nothing left of it several million years after an organism dies. You would have to use an isotope of an element with a much longer half-life and look for it in volcanic rock layers above and below the sediments where the fossil was found, since sedimentary rock can't be radiometrically dated. The reason for this is that sedimentary rock contains particles from rocks of all different ages) p461 |
| * TRUE or FALSE: Fossils can be found in volcanic rock layers. | FALSE: (When volcanic rock is first formed, it is molten lava which would destroy any fossils) p461 |
| * TRUE or FALSE: The age of sedimentary rocks CANNOT be determined by radiometric dating. | TRUE (Sedimentary rocks are made from particles of rocks from many different places that are all different ages) p461 |
| * TRUE or FALSE: If a fossil is found in sedimentary rock that has a volcanic rock layer radiometrically dated at 400 million years below it and another volcanic rock layer dated at 390 million years old above it, the fossil can be assumed to be between 390 and 400 million years old. | TRUE p461 |
| ** The era between 541 and 252 million years ago is called the ____. | Paleozoic (an easy way to remember the order of the eras is that the older the era, the further toward the end of the alphabet it starts with. Paleozoic is older than mezozoic and mezozoic is older than cenozoic) p461 |
| ** The era between 252 and 66 million years ago is called the ____. | Mesozoic (an easy way to remember the order of the eras is that the older the era, the further toward the end of the alphabet it starts with. Paleozoic is older than mezozoic and mezozoic is older than cenozoic) p461 |
| ** The era between 66 million years ago up through the present is called the ____. | Cenozoic (an easy way to remember the order of the eras is that the older the era, the further toward the end of the alphabet it starts with. Paleozoic is older than mezozoic and mezozoic is older than cenozoic) p461 |
| * The collision of two tectonic plates causes the formation of ______. | mountains |
| ** How many mass extinctions have occurred within the last 500 million years? | 5 (Many scientists believe that we are currently at the start of the 6th mass extinction of the Phanerozoic eon, due to humans this time around. If you go back further than 500 million years, there was almost certainly a mass extinction between 2 and 3 million years ago when photosynthesis evolved, turning our atmosphere into one that included oxygen for the first time. Many single-celled prokaryotes couldn't handle oxygen as is the case with obligate anaerobes today) p469 |
| ** TRUE or FALSE: Most of the mass extinctions over the last 500 million years have occurred when global temperatures have been below average. | FALSE (4 out of the 5 mass extinctions have occurred when temperatures have been above average) |
| ** The pattern of speciation that occurs after a mass extinction event could best be described as _____. | adaptive radiation (Adaptive radiation occurs when a species finds themselves in an environment with a bunch of open niches. Darwin's finches found themselves in this situation when they arrived in the Galapagos islands, and quickly evolved into many new species of finches to take advantage of these new niches. Mammals did this after the extinction of dinosaurs, evolving into forms that could take over the niches that dinosaurs had previously occupied, like top predators) p471 |
