Darwin’s Finches: Darwin observed that beak shape varies among finch species. He postulated that the beak of an ancestral species had adapted over time to equip the finches to acquire different food sources. This illustration shows the beak shapes for four species of ground finch: 1. Geospiza magnirostris (the large ground finch), 2. G. fortis (the medium ground finch), 3. G. parvula (the small tree finch), and 4. Certhidea olivacea (the green-warbler finch) the Grants measured beak sizes in the much-reduced population, they found that the average bill size was larger. This was clear evidence for natural selection of bill size caused by the availability of seeds. The Grants had studied the inheritance of bill sizes and knew that the surviving large-billed birds would tend to produce offspring with larger bills, so the selection would lead to evolution of bill size. Subsequent studies by the Grants have demonstrated selection on and evolution of bill size in this species in response to other changing conditions on the island. The evolution has occurred both to larger bills, as in this case, and to smaller bills when large seeds became rare.
Answer: summation
Explanation:
The process which determine if an action potential will be generated or not depends on the combined effects of the signal inputs from multiple sources of synapse or from the repeated signals from the same synapse.
If the input signals reach the threshold voltage, action potential will be generated. (all –or –none principle).Therefore, this process is a determinant of the likelihood of action potential generation and it is called summation.
Summation is the ability to integrate multiple PSPs at multiple synapses.it is the process that determine if an action potential will be generated by combined effects of inhibitory or excitatory signals.
Based on the pathways and voulme of applied stimuli in the presynaptic neuron;
The signals can be temporal summation ( consecutive signals produced from the same synapse)where action potential of high frequency in the PSN generated action potential in the post synaptic neuron, which summate with one another. Or Spatial where signals inputs are from multiple presynaptic cells.
Answer:
adapting can be learning from your environment and ways to survive etc.
Adapting can also go to sexual reproduction to survive diseases unlike asexual reproduction.
