Evolution And Environmental Niches Flashcards
(23 cards)
What is adaptation?
Development of a phenotypic trait that contributes to survival.
What are the three principles of natural selection?
- High species reproductive potential
- Presence of competition
- Survival of few not many
What is speciation?
The process by which different species and apt and evolve to become new species
What are he causes of speciation?
Species becomes divided by a geographical barrier, size differences or distance between populations
What does separation of populations lead to?
Divergence of gene pools and so new species being created
How did continental drift bring about the position of landmasses?
Pangea split into Laurasia and Gondwana. Laurasia became North America, Europe and Asia as a single mass. Gondwana became South America, Africa, India, Australasia and Antarctica
What is the current geological era?
Anthropocene
What are natural selection and evolution rooted in?
Form follows function
What are examples of anatomical adaptations?
Anteater’s tongue, woodpecker’s skull, camouflage of chameleon and octopus, lizard’s ability to drop tail
What kingdom do vertebrates belong to?
Animalia
What phylum do vertebrates belong to?
Chordata
What sub-phylum do vertebrates belong to?
Vertebrata
What are the distinguishing characteristics of animals in Chordata?
Notochord, pharyngeal slits, dorsal hollow neural cord and post anal tail at leat in development
What characteristics do all animals in vertebrata posses?
Vertebral column and notochord at some point in development
What are other sub-phyla in Chordata?
Cephalochordates with a notochord and skull. Urochordates with notochord nd soft body
What are the two patterns of growth?
Isometric and allometric
What is biological scale?
The size and shape of an organism when linke to form and function
What is size and shape of an organism a reflection of?
The demands placed on it by competition and its environment
How does growth occur in isometric growth?
All body parts grow proportionally
How does growth occur in allometric growth?
Different body parts grow at different rates and proportions
Why are eyes of juveniles disproportionate in allometric growth?
Due to precocious development of the CNS
What are the benefits of isometric growth?
Can increase surface area of skin which is required for temperature regulation in amphibians
What are the consequences of isometric growth?
The volume of the body may be too large for the individual to maintain. It may be too heavy for the bone structure or it may require a very large energy intake.
