7. Chapter 6: Adaptation Flashcards
What are adaptations? Examples?
Adaptations are the result of natural selection and they are sometimes complex, have complex functions and a complex history (ex. evolutionary compromises; symbiosis).
Why is our species the only primates choking on food?
Chocking on food is an evolutionary compromise. We have an open space between our soft palate and our epiglottis which gives us a short horizontal tube and long vertical tube. The long vertical tube links to our brain which is important in creating linguistically articulated speech allowing for pronounciation of consonants and vowels. Our vocal chords are found lower in the mouth. The evolution of speech overweighs cost of choking.
Provide an example of Symbiosis.
The ultraviolet portion of the light spectrum attracts nocturnal insects.
What is symbiosis?
The relationship when individuals of two or more species interact with one another
What is mutualism?
A symbiotic interaction in which benefits both species.
What is commensalism?
A symbiotic interaction in which one species benefits but the other species is neither harmed nor helped (neutral)
What is parasitism?
A symbiotic interaction in which one organism, the parasite, derives its nourishment from another organism, its host, which is harmed in the pro-cess.
Describe examples of symbiosis.
Mutualism: Burying beetles transport mites. Burying beetles feed larvae and competition from cadaver and mites use beetles as amino transportation
Parasitism: flatworms can be consumed by humans through fish, particularly raw fish, they will consume vital vitamins in humans
What is the concept of exaptation?
All traits of a living being are not necessarily adaptations to the current environment or an adaptation whose current function is not the one for which the structure initially evolved
What are methods aimed at corroborating or refuting an adaptive hypothesis?
- Direct study of natural selection (e.g. peppered moth, Medium ground finch, human adaptation to altitude)
- Comparative approach and knowledge of phylogenies: indicator that traits have evolved independently or are the result of a common ancestor. (e.g. carnivorous jaws vs herbivore jaws)
- morpho-functional study of a trait (e.g. evolution of fur or feathers) where function is not associated with its origin
Describe the adaptations in the tyrannosauroidea.
In the tyrannosaurus, the smallest species tend to be the oldest.
What is true about adaptations in species? (In fish, in tetrapods, …)
- That species bear characteristics that have evolved in ancestral species.
- The initial function of fins was to stabilize the fish body in its environment; it is an adaptation.
- In terrestrial animals (tetrapods), the limbs that have evolved from fins are used to support the body in an aerial environment. The limbs of the tetrapods are an exaptation for terrestrial mobility (locomotion).
Is the evolution of hair (on elephants, humans, etc.) an adaptation or exaptation to conserve heat?
Conserving heat is an exaptation as hair evolved to lose heat in warm tropic environments and the hair will dissipates and conserve heat more evenly and efficiently
Is the evolution of feathers an adaptation or exaptation for flight?
Feathers is an adaptation for flight as may have been evolved as a sensory function or through intersexual selection.
What is heterochrony?
Changes in the speed or synchronization of the developmental phases. It can sometimes alter the development
speed of the reproductive organs.
