Skills 2-3: Theories of evolution
Darwin and Wallace's theories of evolution
Darwin and Wallace's theories of evolution
Skill 2: List the steps which cause evolution and name the men who first explained it.
Skill 2: List the steps which cause evolution and name the men who first explained it.
Charles Darwin was aboard the HMS Beagle from 1831-1836 as a naturalist. He is most famous for studying the organisms on the Galapagos Islands and developing the currently accepted theory of evolution.
Charles Darwin was aboard the HMS Beagle from 1831-1836 as a naturalist. He is most famous for studying the organisms on the Galapagos Islands and developing the currently accepted theory of evolution.
Darwin waited nearly 25 years to publish his ideas about natural selection and evolution to avoid conflict with those who believed in creationism (the idea that God created all species in their final, unchanging forms). He might have waited longer, had Alfred Wallace not sent his own ideas on evolution to Darwin in 1858 which were nearly identical to Darwin's. Fearing that he would not receive credit for his life's work, he wrote an abstract of his ideas which he published the following year, as "The Origin of Species" on 24 November 1859.
Darwin waited nearly 25 years to publish his ideas about natural selection and evolution to avoid conflict with those who believed in creationism (the idea that God created all species in their final, unchanging forms). He might have waited longer, had Alfred Wallace not sent his own ideas on evolution to Darwin in 1858 which were nearly identical to Darwin's. Fearing that he would not receive credit for his life's work, he wrote an abstract of his ideas which he published the following year, as "The Origin of Species" on 24 November 1859.
Alfred Wallace was a British naturalist and biologist who traveled to Brazil in 1848 where he investigated and collected species for four years. On the way home to England, his ship caught fire and sank. After 10 days, he was rescued by a passing ship, but all of his specimens and notes were lost forever.
Alfred Wallace was a British naturalist and biologist who traveled to Brazil in 1848 where he investigated and collected species for four years. On the way home to England, his ship caught fire and sank. After 10 days, he was rescued by a passing ship, but all of his specimens and notes were lost forever.
Despite his setbacks, he set forth on a new expedition in 1854, this time to the Malay Archipelago which makes up modern day Indonesia and the Philippines. It was here that he solidified his ideas about how species change over time. He sent his work to Darwin for review in 1858. He asked Darwin to forward his work to Charles Lyell, if Darwin found his ideas "sufficiently novel and interesting." The Linnean Society published excerpts from both Darwin and Wallace in August 1858, which was the first publication of either scientist's work on the subject.
Despite his setbacks, he set forth on a new expedition in 1854, this time to the Malay Archipelago which makes up modern day Indonesia and the Philippines. It was here that he solidified his ideas about how species change over time. He sent his work to Darwin for review in 1858. He asked Darwin to forward his work to Charles Lyell, if Darwin found his ideas "sufficiently novel and interesting." The Linnean Society published excerpts from both Darwin and Wallace in August 1858, which was the first publication of either scientist's work on the subject.
Beccaloni, G. W. 2013. Alfred Russel Wallace and Natural Selection: the Real Story. <http://downloads.bbc.co.uk/tv/junglehero/alfred-wallace-biography.pdf
Darwin and Wallace's basic ideas
Darwin and Wallace's basic ideas
Here is an optional Crash Course Video in case you are interested in more of the details about the development of the idea of evolution.
Here is an optional Crash Course Video in case you are interested in more of the details about the development of the idea of evolution.
Genetic variety exists within a species due to sexual reproduction, crossing over during meiosis, and random mutations.
Genetic variety exists within a species due to sexual reproduction, crossing over during meiosis, and random mutations.
There is competition for limited resources.
There is competition for limited resources.
Some organisms have an advantage over others and have higher survival rates. This is called "natural selection" or "survival of the fittest."
Some organisms have an advantage over others and have higher survival rates. This is called "natural selection" or "survival of the fittest."
Those who live longer, produce more offspring, thus passing on the desired trait.
Those who live longer, produce more offspring, thus passing on the desired trait.
Over many generations, the species as a whole, changes its characteristics. This is called evolution.
Over many generations, the species as a whole, changes its characteristics. This is called evolution.
Predict the changes
Predict the changes
Skill 3: What is natural selection's role in evolution?
Skill 3: What is natural selection's role in evolution?
1. Which bird is more likely to survive to have babies?
1. Which bird is more likely to survive to have babies?
2. Which beak length genes will most likely be passed on more?
2. Which beak length genes will most likely be passed on more?
3. What will probably happen to the beak length of these woodpeckers over time?
3. What will probably happen to the beak length of these woodpeckers over time?
4. Can you think of an environmental condition which favors the other bird?
4. Can you think of an environmental condition which favors the other bird?
Here is an example of mimicry. The coral snake and king snake look similar, but only the coral snake is venemous. Due to their similar looks, predators avoid both colorations.
Here is an example of mimicry. The coral snake and king snake look similar, but only the coral snake is venemous. Due to their similar looks, predators avoid both colorations.
Here is a rhyme to help you remember the difference.
Here is a rhyme to help you remember the difference.
Red touch yellow, kill a fellow.
Red touch yellow, kill a fellow.
Red touch black, poison lacks.
Red touch black, poison lacks.
In my opinion, the rhyme below is all you need.
In my opinion, the rhyme below is all you need.
It's a snake...don't touch it!
It's a snake...don't touch it!
NOTE: Snakes are venomous or non-venemous. They are not poisonous. Poisons are ingested (eaten), while venom is injected (snake bite.) Whoever created that image made a mistake and I can't figure out how to crop it out.
NOTE: Snakes are venomous or non-venemous. They are not poisonous. Poisons are ingested (eaten), while venom is injected (snake bite.) Whoever created that image made a mistake and I can't figure out how to crop it out.
*Class activity - Butterfly drawing
*Class activity - Butterfly drawing
Monarch butterflies have warning coloration to indicate to potential predators that they are poisonous. Viceroys are palatable (tasty) to birds, but have a similar coloring which protects them from being eaten. Since they are two separate species, can you predict how the Viceroys came to resemble the monarchs?
Monarch butterflies have warning coloration to indicate to potential predators that they are poisonous. Viceroys are palatable (tasty) to birds, but have a similar coloring which protects them from being eaten. Since they are two separate species, can you predict how the Viceroys came to resemble the monarchs?