[填空题]
A study was completed on the Cistus spg4 .*m:3 r 7daa cdmxvpc1n grjsw0(8n. ofcw.b +s4fku 0u the Mediterranean to look at the relationship between the different white-flowered species. Cistus is a genus of plants that are shrubs and are commonly k fcwu k+.bsu40nown as rockroses.
The cladogram below shows the relationship between species of the Cistus genus and also includes the genera Fumana, Helianthemum, Tuberia and Halimium.
1.1.Determine the number of nodes between the common ancestor indicated by ‘A’ in the diagram and the clade of Cistus with purple flowers.There are nodes
1.2.Identify the genus containing the highest number of species in this cladogram.The genus with the most species is .
1.3.Calculate the percentage of species that belong to the genus that you have named in (ii).it= %.
1.4.Based on this cladogram outline the relationship between Cistus and Halimium species.
2.1.Identify two species that are the only white-flowered Cistus species in their ecosystem type.
2.2.Deduce, with a reason, the ecosystem with the greatest variety of Cistus species.
2.3.Discuss the evidence from the cladogram that ecosystem type is a factor that contributes to evolution.
Log-Bayes factor is a statistical tool. It was used to evaluate the influence of the environment and insolation on three characteristics of Cistus species.
·Environment is the type of ecosystem
·Insolation is the solar energy that reaches a surface
The three factors studied were leaf shape, labdanum secretion and leaf pubescence.
·The leaf shape of Cistus species is linear or ovate
·Labdanum secretion is the resin or gum that is secreted by Cistus species during hot weather
·Leaf pubescence is the fine hair on leaves and stems that helps to keep leaves cool
The table below gives the log-Bayes factor for the relationships between: (i) leaf shape and environment, (ii) leaf shape and insolation, (iii) labdanum secretion and environment, (iv) labdanum secretion and insolation, (v) leaf pubescence and environment, and (vi) leaf pubescence and insolation.
Log-Bayes factor between -0.1 and 1 indicates ‘barely correlated’ between the factors. Log-Bayes factor less than -0.1 indicates ‘evidence against correlation’. The greater the positive log-Bayes factor, the greater the evidence for correlation
3.1.Deduce, based on the log-Bayes values, which factor, environment or insolation, has the strongest correlation with the three characteristics.
3.2.Using all of the data, evaluate the evidence that the environment has been a significant factor in the evolution of the Cistus species.
