Practise classifying organisms, quantifying biodiversity and evaluating conservation strategies from biological and field data.
The sea blush, Plectritis congesta, is a flowering plant that grows on the west coast of North America.
Individual sea blush plants produce fruit that is either winged or wingless. Investigations have shown that this characteristic is controlled by a single gene with two alleles:
- a dominant winged fruit allele
- a recessive wingless fruit allele.
Fig. 3.1 shows the difference in structure between winged fruit and wingless fruit phenotypes.
Fig. 3.1
Early taxonomists classified sea blush plants with winged fruits as a different species to sea blush plants with wingless fruits.
Since this time, evidence from observations and experiments has confirmed that the plants belong to the same species.
Suggest three examples of the evidence obtained that helped to confirm that these sea blush plants belong to the same species.
Researchers measured insect biodiversity on Acacia trees in the African savannah using the following method:
- insecticide was sprayed into each tree
- this killed the insects, which fell onto a sheet below the tree
- the dead insects were collected, identified and counted.
The researchers considered each tree to be a small, distinct ecosystem.
Discuss whether or not an individual tree can be described as a small, distinct ecosystem.
Table 5.1 shows summary statistics for some of the trees sampled in this study. The leaf canopy area is a measure of the size of the tree and the extent of its leaf cover.
Table 5.2 shows the diversity and abundance of some different taxonomic groups of insects in the study.
Table 5.1
Table 5.2
Select, from Tables 5.1 and 5.2, a name to fit the following taxonomic groups:
a genus
a species
This study was carried out in Mkomazi Game Reserve in Tanzania.
Suggest how research into insect diversity on Acacia trees is relevant to the conservation of bigger animals in the reserve, such as elephants.
The aye-aye, Daubentonia madagascariensis, is a mammal, native to Madagascar. Aye-ayes are active at night and make their nests high up in trees. They feed on insect larvae in the trunks of trees.
Fig. 1.1 shows an aye-aye.
Fig. 1.1
The International Union for Conservation of Nature (IUCN) categorises the aye-aye as endangered. This means that the aye-aye has a very high risk of becoming extinct in the wild.
Name the domain to which the aye-aye belongs.
State one reason why aye-ayes may have become endangered.
Suggest ways in which zoos may be able to protect this species from extinction.