2nd Form Evolution Flashcards
What do ammonite, snail, limpet, slug and nautilus have in common
-all Marine gastropods
-no backbones
-soft bodies
How are ammonite ,snail,limpet,slug,nautilus different?
Snails and slugs have evolved to live on land as well as marine environments
Shape of shells
Number of tentacles
Can be many different colours and patterns
What links ammonite, snail, limpet, slug, nautilus
They have all been around for millions of years
What is evolution
Evolution is the idea that all species on earth have gradually developed over millions of years
What did evolution start with
Unicellular organisms (made up of only single cells)
What is natural selection
The idea that natural events can act upon plants and animals to select those individuals who are best adapted to current conditions
Modern giraffes have long necks-their ancestors did not
Using this example, how did evolution occur via natural selection
Some giraffes had long necks, and they were the ones who could reach food, therefore the giraffes with long necks survived rather than the ones with short necks
What does peer review mean
Other experts who aren’t connected to you review your work
Give two reasons why Darwin’s theory was only gradually excepted
1- the theory challenged the idea that god created everything (creationism)
2-there wasn’t enough evidence to convince scientists at the time that the paper was published
What are examples of evidence for Darwin’s theory
Fossils
DNA analysis and classification
Antibiotic resistant bacteria
Extinction means…
No individuals of species alive in the world
Evidence to show dinosaurs existed
Fossila
State 3 theories for the extinction of the dinosaurs
Super volcano, asteroid, climate change
Describe other factors that could lead to extinction of a species
Poaching, sudden changes in environment, destruction and loss of habitat, disease outbreaks, new predators
Biodiversity is…
The variety of different species living in a habitat
What can be done to protect endangered species and prevent extinction
Captive breeding programs
Conservation of habitats
Preservation of habitats
Education of these topics
A reduced amount of light + heat could have caused extinction of plants. How?
Plants need light and heat to photosynthesise
How could extinction of plants cause some animals to go extinct
Loss of food source
Two reasons why animals may become extinct
Poaching
Loss of habitat
How many mass extinctions have occurred over the last 300 million years
3
How do we know what animals lived on earth millions of years ago
Fossils
How many years ago did the most recent mass extinction occur
65 million years ago
How many million years ago did humans first use fire
3 million years ago
