Taxonomic Hierarchy

In biology, every organism has several taxonomic classifications; these classifications are taken from the taxonomic hierarchy. This hierarchical tree displays how all Earth organisms are related to each other.

To illustrate this hierarchical tree, imagine a daffodil, ladybug, goldfish, human, cat, fox, jackal and dog.

Regio
Out of the three Domains that make up Life on Earth, the Eukarya is the most diverse domain. (The other two Domains are that of the Archaea, a group of single-celled organisms, and that of the Bacteria, very small organisms whose cells do not have a nucleus.)

This Eukarya Domain includes all organisms with complex cells, or a single cell with a complex structure; in these cells the genetic material is organized into chromosomes in the cell nucleus. Obviously, this includes the life forms listed above.

Regnum
The Eukarya Domain is made up of Kingdoms; the Animal Kingdom being the most well known. This Kingdom includes all the animals listed above, from ladybug to dog, but excludes a plant like the daffodil.

Phylum
The Animal Kingdom is made up of Phyla; the Phylum Chordata is one of the most interesting Phyla because it includes all vertebrates. That is to say, all mammals, fish, amphibians, reptiles, birds – to name a few – are part of this Phylum. Note that the ladybug is not part of this Phylum.

Classis
The Chordata Phylum is made up of Classes; the Mammal Class being the most dominant on Earth. Humans, cats, foxes, jackals, dogs and all other animals who suckle their young are part of this Class. This excludes the goldfish.

“If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man.”
– Mark Twain

Ordo
The Class of Mammals is made up of Orders; if we take the Order of Carnivora, the carnivores, we would exclude human beings (who are the story telling member of the Order Primates, in the Family of the Hominidae, of the Genus Homo). This leaves us with the cat, fox, jackal and dog.

Familia
The Order of Carnivora is made up of Families; the fox, jackal and dog are part of the Family Canidae. That is, all dog-like animals. This excludes the cat.

Genus
The Family Canidae is made up of Genera. (The term comes from the Latin genus meaning “descent, family, type, gender”; from the Ancient Greek: γένος, “race, stock, kin”.) In our example, the fox is part of a different Genus than the jackal and the dog.

Species
The Genus Canis is made up of Species; the most widely accepted definition of a species is ‘the largest group of organisms capable of interbreeding and producing fertile offspring’. That brings us to the difference between a jackal (canis aureus) and a dog (canis lupus), who are part of the same genus, but are different species.

“Outside of a dog, a book is man’s best friend. Inside of a dog it’s too dark to read.”
– Groucho Marx

Assortative Mating‏

In human genetics, assortative mating‏ is a form of non-random mating in which pair bonds are established on the basis of phenotype i.e. observable characteristics, which is thought to underlie mate selection in a variety of animal species as well.

“I had a patient once who dreamed she kept her husband in the deep freeze except for mating. Lots of men feel that way.” – Robert Johnson

Two Coccinella Septempunctata, or Ladybirds mating

In human relations, the assortative mating‏ process may lead a person to choose a mate according to religious, cultural, or ethnic preferences, professional interests, or physical traits.

Positive assortative mating, or homogamy, exists when people choose to mate with persons similar to themselves; this type of selection is very common.

Negative assortative mating is the opposite case, when people avoid mating with persons similar to themselves.

“All nature’s creatures join to express nature’s purpose. Somewhere in their mounting and mating, rutting and butting is the very secret of nature itself.” – Graham Swift

Fisherian Runaway‏

The Fisher’s runaway process for species development consists of the two phases which he outlines in his genetical theory of natural selection:

Phase 1

Female preferences initially evolve because the preferred traitis favored by natural selection and hence the offspring are more likely to carry the beneficial trait.

Whenever appreciable differences exist in a species, which are in fact correlated with selective advantage, there will be a tendency to select also those individuals of the opposite sex which most clearly discriminate the difference to be observed, and which most decidedly prefer the more advantageous type.

Phase 2

Once female preferences exist, males with the trait are even more fit (both a natural and a sexual selection advantage). There will then be an ever increasing selective force favouring stronger preferences and more extreme traits (Fisher’s runaway process).

The further development of the character trait will still proceed, by reason of the advantage gained in sexual selection, even after it has passed the point in development at which its advantage in Natural Selection has ceased.

Summary

1. Males and females have different constraints on reproduction:
   1. Females tend to be limited by fertility,
   2. Males limited by mating success;
2. This disparity leads to:
   1. Males having a much larger variance in reproductive success;
   2. Female “choosiness” (the bases for which are not always clear);
3. This choosiness leads to extreme male traits, often at odds withmale viability fitness.

Manakin Bird

The manakins are a family, Pipridae, of unique small suboscine passerine birds. The family contains some 60 species. They are distributed through the American tropics. The name is from Middle Dutch mannekijn meaning ‘little man’.

The Male Helmeted Manakin or Antilophia Ggaleata

The genus Tyranneutes comprise the smallest manakins, the genus Antilophia are believed to be the largest. They are compact stubby birds with short tails, broad and rounded wings, and big heads. The bill is short and has a wide gap. Females and first-year males have dull green plumage; most species are sexually dichromatic in their plumage, the males being mostly black with striking colours in patches, and in some species having long, decorative tail or crown feathers or erectile throat feathers. In some species, males from two to four years old have a distinctive subadult plumage.

The syrinx or so-called voicebox is distinctive in manakins, setting them apart from the related families Cotingidae and Tyrannidae. Furthermore, it is so acutely variable within the group that genera and even species can be identified by the syrinx alone, unlike birds of most oscine families. The sounds made are whistles, trills, and buzzes.

The Manakin bird is famous for its so-called tap-dance ‘moonwalk’ along branches of trees. The male tries to attract a female by moving at quite a pace along twigs and branches while keeping an eye on a potential mate. This dance as it were involves incredibly fast movements and composure of the claws as it moves from left to right and visa versa.