D: Biology = Changes in Living Systems 2.4 Adaptations and 2.5 Evolutionary Theory Flashcards
(122 cards)
What year did Charles Darwin set sail on the HMS Beagle?
1831
What was Charles Darwin’s role on the HMS Beagle?
Naturalist
What did Darwin collect during his voyage on the HMS Beagle?
A huge number of species of plants and animals
What is the name of the volcanic islands that fascinated Darwin?
Galapagos Islands
What type of regions do the Galapagos Islands have?
Different climatic regions
What did Darwin observe about the organisms on the Galapagos Islands?
Strong similarities between organisms with different adaptations
What did Darwin hypothesize about the variety of finches he found?
They must be related
What are the three types of beaks observed in Galapagos finches?
- Thick beaks for crushing hard seeds
- Parrotlike beaks for eating fruit
- Slim beaks for catching insects
Fill in the blank: Darwin suggested that the finches all came from a common _______ ancestor.
seed-eating
How did Darwin believe finches arrived at the Galapagos Islands?
They were blown to the islands from the mainland
What happened to the finch populations after arriving on the Galapagos Islands?
Their populations soared due to abundant food and lack of predators
What caused the finch population to face a lack of food?
The habitat lacked enough seeds to support the large population
What kind of variation exists within finch populations according to Darwin?
Variation in many traits including beak characteristics
What happens to finches best suited to consume available food sources on the island?
They survive to breed with other successful birds with similar beaks
What is passed on to the offspring of finches with advantageous beak types?
Genes for their beak type
What resulted from generations of finches adapting to specific food sources?
Lines of birds that were each adapted to collecting a specific food source
What differences can be observed in the distinct lines of finches?
Beak shape, food eaten, mating behaviour, and other differences
What environmental pressure influenced the adaptation of finches?
Limited food
Fill in the blank: Over many generations, several new finch species ______ that were well-adapted to eating different foods than their ancestors did.
developed
True or False: The finches’ adaptations were a result of random genetic mutations.
False
What year did Charles Darwin publish his book, On the Origin of Species?
1859
What does the term ‘evolution’ literally mean?
Unrolling or opening out
In a biological context, what does evolution refer to?
A change in the characteristics of a population over time
What did Darwin propose about all life on Earth?
All life shares a common ancestor