Evolution Study Guide
How many of species of organisms on Earth have scientists identified
1.6 million
Which scientists both produced the same explanation for how evolution occurred in 1858?
Alfred Russel Wallance ( another British biologist) and Darwin
What would happen without variations
All the members of a species would have the same traits and the same chance of surviving and reproducing
What is the following an example of ? Some turtles may not find enough to eat. A slower turtle may be caught by a predator, while a faster turtle may escape. Only a few turtles will survive and reproduce
Competition
What did Darwin do after Him and Alfred Russel Wallance proposed the same explanation for how evolution occurs in 1858
Darwin described his explanation in his book The Origin of Species the next year
What is the following an example of? Monkey flowers are plants that don't normally grow in soil that has a high concentration of copper. However, because of genetic variation, some varieties of monkey flower now grow near copper mines. Here is the steps, Monkey flowers grow successfuly healthy in in polluted soil. Copper seeps into the soil around the copper mine. Most Monkey flowers can't grow in this polluted soil and so they begin to die.Some monkey 🌺 have gentetic variations that alllow them to survive and reproduce in copper contaminated soil. Then the pollution resistant Monkey 🐒 🌸 becomes more common.
Environmental change
What are three observations that Darwin made during the Beagles Voyage ?
Finches beaks, sloths, and turtles
What is an example of artificial selection that Darwin had done
He had bred pigeons with large, fan shaped tails. By repeatedly allowing only those pigeons with many tail feathers to mate, Darwin produced pigeons with two or three times the usual number of tail feathers
What were some important differences between Galapagos organisms and those found in South America did Darwin see between the organisms (about Iguanas)
Iguanas on the Galapagos Islands have large claws that allow them to grip slippery rocks so they can feed on seaweed. Iguanas on the mainland have smaller claws that allow them to climb trees so they can eat leaves
What do changes in the environment affect?
Individuals, organisms with specific traits, or entire species. Changes that affect an organism's ability to survive , and therefore reproduce, lead to natural selection
What were some of the similarities that Darwin discovered between Galapagos organisms and those found in South America
Many of the birds and plants on the Islands resembled those on the mainland
The process by which individuals that are better adapted to their environment are more likely to survive and reproduce more than other members of the same species ( the best that survive)
Natural selection
Does competition always involve physical fights between members of a species
No it is usually indirect
What was Darwin's proposal?
Over a long time, natural selection can lead to change. Helpful variations may accumulate in a species, while unfavorable ones may disappear
What causes natural selection?
Overpopulation, competition, and Variation
What is this called? Darwin knew that most species produce far more offspring than can possibly survive
Overproduction
a well-tested concept that explains a wide range of observations
Scientific theory
What is the following an example of? Darwin observed that some variations make individuals better adapted to their environment. Those individuals are more likely to survive and reproduce
Selection
Why do members of a species must compete with one another to survive
Since food , space , and other resources are limited
A group of similar organisms that can mate with each other and produce fertile offspring that can also mate and reproduce.
Species
What did Darwin propose in his book The Origin of Species?
That evolution occurs by means of natural selection
What did scientists later learn
That variations can result from changes in genes and the shuffling of different forms of genes when egg and sperm join. Genes, such as those for hair color and height, are passed from parents to their offspring. Only traits that are inherited, or controlled by genes that are passed on to offspring, can be acted upon by natural selection
How did Darwin observe many unusual life forms in the Galapagos Islands
The Beagle made many stops along the Atlantic and Pacific coasts of South America. From the Pacific coast, the ship traveled west to the Galapagos Islands
What was Darwin's book called?
The Origin of Species
What happens when many offspring are produced?
There are not enough resources such as food ,water 💧, and living space 🏠 for all of them
Any difference between individuals of the same species
Variation
What is the following an example of? Sea turtles may differ in color, size, the ability to swim quickly, and shell hardness
Variation
How do more members of the species have the helpful characteristic after many generations?
When the species survive their offspring may inherit the helpful characteristic. The offspring, in turn , will be more likely to survive and reproduce, and pass the characteristic to their offspring
Does the environment select organisms with helpful traits to become parents of the next generation
Yes
Who is Charles Darwin?
a naturalist (a person who observes and studies the natural world) who was on the British ship HMS beagle that set sail from England on a five year trip around the world in 1831
Adaptation
a trait that increases an organism's ability to survive and reproduce
Darwin studied the offspring of domesticated animals that were produced by ........................ in an effort to understand how evolution might occur
artificial selection
What is an example of adaptation for finches
beak shape
What do birds with long, pointed, sharp beaks eat
cacti (Cactus Ground Finch)
the process of change over time
evolution
What do birds with short,thick beaks eat
hard seeds and nuts (Medium ground finch which beaks crush seeds)
Over the next 20 years, after Darwin consulted with other scientists and gathered more info, based on his observations what was Darwin's answer to how animals changed
he reasoned that plants or animals that arrived on the Galapagos Islands faced conditions that were different from those on the nearby mainland
What is an example of how Darwin was puzzled by some of the fossils he observed
he saw fossils that resembled the bones of living sloths but were much larger in size. He wondered what had happened to the ancient, giant ground sloths
What did Darwin want to know about what he was convinced about
how organisms change
What do birds with narrow, pointed beaks grasp
insects (Small Tree finch)
What did Darwin see/ observe during the voyage?
insects that looked like flowers and he observed sloths, slow moving animals that spent much of their time hanging in trees
What is the color of each Iguana an adaptation to?
its habitat so that it can blend in its habitat which can cause them to live longer
Darwin thought that a process similar to artificial selection might happen in ......, but he wondered what natural processes selected certain traits
nature
Is the exact number of species known
no because many areas of earth have not yet been studied
What happens in Artificial selection
only the organisms with a desired characteristic, such as color are bred
What did Darwin compare along his journey
organisms from the Galapagos Islands to organisms that lived elsewhere and he also compared organisms living on the different islands
What do birds with short, hooked beaks do
tear open fruit (Vegetarian tree finch)
What was Darwin's hypothesis?
that Species change over many generations and become better adapted to new conditions
What did a government official in the Islands tell Darwin?
that he could tell which island a tortuous came from just by looking at its shell
What do scientist know today that Darwin didn't
that organisms are even more diverse than Darwin thought
What was Darwin convinced about after he had thought about what he had seen during his voyage on the Beagle
that organisms change over time
What did Darwin become convinced about
that species do not always stay the same. Instead, he thought species could change and even produce new species over time
When Darwin returned to England, what did he learn
that the different birds were all finches
From the evidence he collected, what did Darwin conclude about the organisms on the Galapagos Islands
that they had changed over time
What did Darwin conclude about the Finch species
that they were all related to a single ancestor species that came from the mainland. Over time, different finches developed different beak shapes and sizes that were well suited to the food that they ate
What did Darwin begin to think about the Galapagos island species and the South American species
that they were somehow related. Perhaps, he thought, the island species had become different from their mainland relatives over time
What was Darwin amazed by
the diversity of living things that he saw during the voyage
What does the word fossil mean in the sentence, Darwin saw fossils of animals that had died long ago
the preserved remains or traces of an organism that lived in the past
What were Darwin's ideas often referred to?
the theory of evolution
What were some of the differences between organisms on the different Galapagos Islands ?
the tortoises on one Island had dome shaped shells, but those on another island had saddle shaped shells
The structure of each bird's beak is an adaptation to ..............
the type of food the bird eats
What could Darwin not explain?
what caused variations or how they were passed on
What did Darwin wonder during the voyage
why living things were so different from those in England
Were birds different from one Island to the next?
yes