Title: InkBiology / Classification, biodiversity and conservation
On every note of this deck, unless a note says otherwise:
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Front: DEFINE
Define: In situ conservation.
Back: Conserving a species in its natural habitat, so that the community and the conditions it is adapted to are conserved with it.

Front: DEFINE
Define: Species richness.
Back: The number of different species in a community.

Front: DEFINE
Define: Endangered species.
Back: A species at high risk of extinction in the wild, as assessed against criteria such as the IUCN Red List's.

Front: DEFINE
Define: Ex situ conservation.
Back: Conserving a species outside its natural habitat, in a zoo, a botanic garden, a seed bank or a captive breeding centre.

Front: DEFINE
Define: Taxon.
Back: Any one group in that hierarchy: Mammalia, Primates and Homo are all taxa.

Front: CHECK YOURSELF
A national park protects an area of savannah containing a population of about 400 black rhinoceros. Poaching has risen and 30 animals were killed last year. A donor offers enough money either to double the number of rangers patrolling the park, or to establish a captive breeding herd of 40 animals in a fenced sanctuary elsewhere. Discuss the biological arguments on each side.
Back: The case for the rangers, in situ. The 400 animals in the park are a far larger gene pool than any captive herd could be, so keeping them alive conserves genetic diversity that cannot be recreated once it is gone. They are in the habitat they are adapted to, with the plants they browse and the community they belong to, and natural selection continues to act. Protecting the park protects everything else living in it at no extra cost. The threat here is poaching, which is precisely the threat more rangers address; the habitat itself is intact, so nothing else is currently limiting the population.
The case for the sanctuary, ex situ. Forty animals behind a fence are far easier to protect, and a catastrophe in the park, whether an escalation in poaching, a disease outbreak or a drought, would not take them with it. Breeding can be managed with a studbook so that the least related animals are paired, and reproduction can be assisted. Rhinoceros are large, slow-breeding and easy to find, which makes them poor candidates for protection by patrol alone.
Against the sanctuary. Forty founders is a bottleneck: alleles present in the other 360 animals are lost at the moment of selection, and inbreeding will raise homozygosity in the herd within a few generations. It costs a great deal per animal. It does nothing whatever about the poaching, so the wild population continues to fall while the herd is established, and any future release goes back into the same danger.
Against the rangers. Patrolling treats the symptom. If the demand for horn and the poverty that supplies poachers are untouched, more rangers raises the cost of poaching without ending it, and the money runs out eventually.
A defensible conclusion. Spend it on the rangers. The habitat is intact and the population is large, so the only thing currently reducing it is killing, and the intervention that stops killing conserves 400 animals and their alleles rather than 40. The sanctuary would be the right answer if the habitat itself were being lost, or if the population had already fallen so low that protection in place could not be relied on. Either answer can earn full marks if it argues from population size, genetic diversity and the nature of the threat rather than from preference.

Front: CHECK YOURSELF
A conservation officer samples two ponds. Pond 1 contains four invertebrate species with 50, 30, 15 and 5 individuals. Pond 2 contains six species with 85, 5, 4, 3, 2 and 1 individuals. Using d = N(N − 1) ÷ Σn(n − 1), calculate the index for each, and explain why the pond with more species scores lower.
Back: Pond 1. N = 50 + 30 + 15 + 5 = 100, so N(N − 1) = 100 × 99 = 9900. The terms are 50 × 49 = 2450, 30 × 29 = 870, 15 × 14 = 210 and 5 × 4 = 20, which add to 3550. d = 9900 ÷ 3550 = 2.79.
Pond 2. N = 85 + 5 + 4 + 3 + 2 + 1 = 100, so N(N − 1) = 9900 again. The terms are 85 × 84 = 7140, 5 × 4 = 20, 4 × 3 = 12, 3 × 2 = 6, 2 × 1 = 2 and 1 × 0 = 0, which add to 7180. d = 9900 ÷ 7180 = 1.38.
Pond 2 has six species to pond 1's four, and scores less than half as high. The reason is evenness. In pond 2, 85 of the 100 individuals belong to a single species, so two individuals picked at random are very likely to be the same species and the denominator is dominated by the 7140 term. The five other species are present but barely. One of them is a single animal, contributing 1 × 0 = 0 to the sum, which is the arithmetic noticing that a species represented once adds nothing to the chance of drawing two alike.
Pond 1 spreads its hundred individuals across four species with no single one taking more than half, so the sum is far smaller and the index far larger.
The ecological reading is that pond 2 is probably a stressed or recently disturbed pond in which one tolerant species has taken over and the rest are hanging on. Species richness alone would have called it the better pond.

Front: DEFINE
Define: Analogous structures.
Back: Structures with the same function and different origins, produced by convergent evolution.

Front: DEFINE
Define: Phylogeny.
Back: The evolutionary history of a group: which lineages split from which, and in what order.

Front: CHECK YOURSELF
A student writes: 'Whales are more closely related to fish than to cows, because whales and fish both live in water, have streamlined bodies and swim using fins.' Explain what is wrong with the reasoning, and describe two kinds of evidence that would settle the question.
Back: The reasoning is phenetic: it groups by resemblance without asking where the resemblance came from. Streamlining, fins and an aquatic life are what any large animal that hunts in open water ends up with, whether it started as a fish or as a land mammal. They are analogous features produced by convergent evolution, and analogy is evidence of a shared problem rather than a shared ancestor.
Look at the structures properly and the argument reverses. A whale's flipper contains the pentadactyl limb, with one upper arm bone, two forearm bones, wrist bones and five digits, which is homologous with the limb of a cow, a bat and a human, and has no counterpart in a fish's fin. Whales also have lungs, a four-chambered heart, hair and mammary glands.
First kind of evidence: compare base sequences. Sequence the same gene, or the whole genome, in a whale, a cow and a fish and count the differences. The whale and the cow come out far closer, and in fact the closest living relatives of whales are hippopotamuses.
Second kind: compare proteins, either by counting differences in the amino acid sequence of a protein such as cytochrome c or haemoglobin, or by an immunological test in which antiserum raised against whale serum proteins gives far more precipitate with cow serum than with fish serum.
Both kinds of evidence are counts of differences in molecules that all three animals possess, so neither of them can be fooled by an adaptation to water.

Front: DEFINE
Define: Extinct in the wild.
Back: A species surviving only in cultivation, captivity or as a population well outside its past range.

Front: DEFINE
Define: Phenetic classification.
Back: Grouping organisms by observable similarity, without regard to how they are related.

Front: SPOT THE ERROR
Say what is wrong with this claim:
Humans evolved from chimpanzees.
Back: Chimpanzees are not our ancestors but our cousins. The two lineages separated from a shared ancestral population six to eight million years ago, and both have been changing ever since. A phylogeny is a record of splitting, with no direction and no finishing line.

Front: DEFINE
Define: Species diversity.
Back: Richness and evenness together, usually expressed as an index.

Front: DEFINE
Define: Binomial.
Back: The two-part international name of a species: genus then specific name, italicised, genus capitalised.

Front: DEFINE
Define: Genetic diversity.
Back: The number of different alleles present in the gene pool of a population or species.

Front: DEFINE
Define: Species evenness.
Back: How equally the individuals are shared out between those species.

Front: DEFINE
Define: Taxonomy.
Back: The naming and classifying of organisms into a hierarchy of groups.

Front: DEFINE
Define: Phylogenetic classification.
Back: Grouping organisms so that each group contains a common ancestor and all of its descendants.

Front: SPOT THE ERROR
Say what is wrong with this claim:
If a species is in trouble, breed it in a zoo and put it back.
Back: A zoo holds a few dozen large animals, far too few to keep a species' alleles, so what comes out is less varied than what went in. Captive animals often cannot hunt or navigate, and a release needs a habitat: if the cause of the decline remains, so does the problem.

Front: SPOT THE ERROR
Say what is wrong with this claim:
The habitat with the most individuals in it is the most diverse.
Back: Abundance is not diversity. A hectare of ryegrass ley holds enormous numbers of organisms belonging to very few species. Diversity is how many species there are and how evenly the individuals are shared between them, which is what an index is built to measure.

Front: DEFINE
Define: Homologous structures.
Back: Structures with the same underlying plan, inherited from a common ancestor, whatever they are now used for.