Tag Archives: taxonomy

The king lizard whale

This weeks bad cast doesn’t really look like a fossil, yet it may be from a creature you might recognise.

 

A very very poor quality cast. Those pesky fossil cast dealers.

A very very poor quality cast. Those pesky fossil cast dealers. Doesn’t look like much, does it?

 

I nearly took the photo this way by mistake;

 

Has someone made a cast of a banana?

Has someone made a cast of a banana?

 

Even worse, I almost took the photo this way;

 

Well. Good job I didnt take the photo this way.

Well. Good job I didnt take the photo this way. Otherwise, this could have been mistaken for a cast of something unimaginable. 

Shocking. Not the shape of the fossil (which is a little), but the quality. How can this be sold as a cast of a ‘real’ fossil? It has. Frustratingly it was 108 years ago, so the dealers cannot be challenged by trading standards. There is no time travelling ombudsman. (Now there’s a cool job.)

This is actually a cast of a fossil tooth! The tooth does exist somewhere, but you wouldn’t be surprised to know that there is no information with this specimen about the original fossil. That would be giving us too much!

The label names the tooth as belonging to Zeuglodon cetoides. This extinct beast is actually one you may recognise; Basilosaurus cetoides. It’s an amazing creature, with an interesting history.

In the earl-1800s, huge fossil bones had been discovered in the sediment of the American South. Huge, and fairly common, these had been used as furniture! A couple of bones were sent to the American Philosophical Society for identification. (The American Philosophical Society was set up in 1743 by Benjamin Franklin and John Bartram and early members included three presidents of the United States of America).

The anatomist who looked at the bones (mainly the bones from the spine; the vertebra), Richard Harlan, compared them to the (then) recently discovered dinosaur bones of Megalosaurus and Iguanodon. Harlan thought they looked very similar, but bigger. So he named the creature ‘Basilosaurus‘ meaning ‘king lizard’.

Was this another type of giant extinct lizard? Another new dinosaur discovered? Nope.

Harlan visited England and took some of his newly described Basilosaurus specimens with him to show to the great Richard Owen. (Richard Owen was an incredible British  comparative anatomist who was able to identify an extinct animal by one bone. He was brilliant, but he was also very arrogant, egotistical and deceitful.) Owen looked at the fossils and there were traits that looked like a mammal, and lots of similarities to whales. He renamed the giant ‘Zeuglodon‘ and the American anatomist agreed.

However, there are rules when we name animals and plants (and bacteria). Them rules are there for a reason. The rules of taxonomy are there to make sure that an organism doesn’t have five different scientific names. It also gives priority to the first name given. So in the case of this big whale, it was scientifically described as Basilosaurus before it was called Zeuglodon, so Basilosaurus takes precedent.

This tooth belonged to this whale that lived during the Eocene (around 40 million years ago). About as long as 4 double decker buses, it was a heft animal! As you can’t really see, the teeth were quite chunky and pointy; the shape, and that one fossil had a stomach full of fish indicate that they fed on fish in the oceans. Closely related to modern whales, the Basilosaurus were not their ancestors; this group and the group of modern whales shared a common ancestor that lived around 50 million years ago.

A delightful little sketch of two Basilosaurus. Big, long, whales. Lovely. (Image from here)

A delightful little sketch of two Basilosaurus. Big, long, whales. Lovely. (Image from here)

Beneath this shockingly bad cast is the tale of an whale that once swam in the oceans millions of years ago. Fossils, and potentially casts of fossils, reveal such awesome clues to forgotten worlds. Many of the bad casts in this series do not give the original fossil any thing to get excited about. This bad cast is no exception.

 

 

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Beginners Guide to Taxonomy: How to classify your Kalla-Wagga

The fire crackles in the jungle as small fragments of glowing ash float upwards. My eyes follow one piece as it flutters this way and that, and I watch as the glow slowly fades and I meet the billion stars above. The air is cool at night. I hear people in the camp quietly talk and laugh. We are in a small clearing in the jungle surrounded by black trees, with a thin path meandering into nothingness off to my left. I become lost; mesmerised by the stars. A sudden crack of a branch followed by a heavy thud brings me back. People group together as we hear some hurried rustlings in the trees above and slapping sounds fading out into the jungle. The group stay together. Silence.

The local woman, Sha’re, stands up, her foot crunching down softly on crispy leaves. A bird screeches in the blackness of the jungle as she raises her right arm, still holding her spear, and quietly says “Kalla-Wagga, Kalla-Wagga”. Her eyes look sad as she scans the trees above. She knows this creature and she has a name for it.

As a tight group we slowly inch towards the dark outline. The night is eerily still and the jungle silent. My heart pounds as I see the creature for the first time. Lying there, it doesn’t move. The arms are splayed above its head, its hairy back curved accentuating the knobbly vertebrae poking out. It is dead. Its large lifeless brown eyes look back at us. It is the most wonderfully odd creature I’ve ever seen.

The creature is clearly a male. Standing he would have reached a little above my hips, so he’s just under a metre tall. He has thick bristles of jet black hair covering his body, apart from the bottom of his back; here he has no tail, but a tuft of long, thick stands of lighter brown hair splayed out and upwards like a reject from the 80’s. The breast area is bare of hair, exposing the Kalla-Wagga’s small nipples.

The head has extremely quirky features. It has incredibly large pink ears. Directly behind each is a pink pouch on the skull; no hair on these domed oval pouches, they are raised out from the skull and appear to be more fatty then the surrounding head. Its mouth lays open, exposing its four curved incisors, small canines, pointy premolars and quite flat molars glistening slightly with the fire. Rolled out along the ground was the tongue, an enormously long tongue!

This was not the most striking feature of the creature. It had a ginormous ass! Very round, bare and very, very smooth skin, with two circular red markings near the top of each buttock. At the top of the legs near the hips there are large flaps of fairly thick bare skin.

I stare at this creature looking at every little detail, trying to take it all in. I jump as a soft hand touches my shoulder. Sha’re stands next to me. “There are stories,” she says in a low, quite voice, “of demons living in the jungle. Demons with glowing white faces and fiery red eyes.” A little smile curls her lip upwards. “Do not worry. They are just stories. We tell them to the children to keep them out of the jungle at night. We say, ‘if you go into the jungle at night, the Kalla-Wagga will get you.’ They never go into the jungle.”

She leads me back to the fire. We sit and Sha’re begins to tell me more about this creature, her Kalla-Wagga. They appear to spend most of their time in the trees foraging for their food in the higher canopy. This animal has a unique strategy for feeding; it uses its rather oversized ears, which it flaps loudly as they slowly climb from branch to branch. The loud thudding of the ears disturbs the little mini-beasts and small animals hiding up there, which the Kalla-Wagga swiftly gobbles down with the aid of its super long, super sticky tongue.

The strange big eared creature, with its extra large arse at home in the high canopy of the Congo rainforests.

The strange big eared creature, with its extra large arse at home in the high canopy of the Congo rainforests.

That was just one use of those iconic ears. The other use of the ears have are bizarrely linked to the big arse of the creature. Once a year, on the first new moon of August, all groups from the surrounding area congregate in their hundreds. Half way up a large mountain, mostly covered by cloud, is a small opening. So small you would miss it if you weren’t looking; but big enough for a Kalla-Wagga to walk through. Once through, the males leave the females near the entrance and make their way deeper inside the cave until they reach a chamber; an enormous chamber. In the pure darkness you can hear the males shuffling around, appearing to find their own place; their own spot. The shuffling stops and the Kalla-Wagga does not make a sound. Out of the darkness, it seems a bright white face with glowing red eyes has just appeared, and another, and another, and a slap! The chamber is now full of faces and slaps.

Here, deep inside the cave, you really would think there were demons living there. It is actually not scary, but quite the opposite; it is the beautifully unusual mating ritual of the Kalla-Wagga. Once a year all members from the troops around this mountain meet to show off their best bits to find a mate. The males bend over, feet flat on the ground, legs straight and rear ends firmly up in the air. Tiny florescent pigments in the oversized buttocks begin to glow, creating a very large round white face, with piercing red eyes. Fluorescent pigments in the spiky hairs at the bottom of the Kalla-Wagga’s back also glow a bright yellow. The large flaps on skin on the hips begin to slap their own buttocks creating soft slapping sounds. The point of this self-flagellation becomes immediately apparent; the flaps move onto the buttocks and off the buttocks in a rhythm, blacking out the bright florescent display; it creates a beautiful hypnotic spectacle. Evidence of the ‘beauty’ of this bizarre display is shown by the female’s excited howls echoing around the chamber of the cave.

Coupled with the display of rear ends, the males begin to thud their large ears on the oval pouches on the heads. The thuds appear to be in tune to their dancing bottoms. They are low and resonate through the chamber. Astonishingly each individual has its own rhythm, and even more astonishingly a female can focus on one individual! The females chose their favourite display and pull their chosen suitor off to another section in the cave. Led by the luminescent buttocks, the two lovers find a quiet spot to mate. But this is no quick frolic in the dark. These animals take their time, for such intimacy is only enjoyed once a year. As the sun rises the exhausted couples exit the cave, and with a final few slaps of their ears they leap off to their home territory. Perhaps they will meet again. Perhaps not.

What kind of creature is the Kalla-Wagga and where does it fit on the enormously diverse and beautiful tree of life? Sha’re helps me obtain permission to borrow the dead Kalla-Wagga and he flies with me, safely stored for the long journey home.

I search through museum collections around the world and brry myself in glorious books about hairy creatures from the Congo. This is a new animal never seen before by science. The creature I have, now staring back at me ghoulishly from its eternal formaldehyde home, is the type specimen for this species; the specimen which is the first of this species to be discovered, described and named. But what species is it? How do I know what this enigmatic creature is and how the heck does someone classify it?!

We begin our quest for classification at the very beginning; the largest group, the Domain. All life on Earth (almost) fits comfortably under three Domains; Archaea (single celled organisms), Bacteria (organisms without a nucleus) and Eukarya (organisms which have a nucleus, including all plants and animals). It is safe to say the Kalla-Wagga belongs with the Eukarya, along with all the plants and animals on the planet, mainly because we don’t need a microscope to see the creature.

Awesome. So we know the Kalla-Wagga is a eukaryote. That was easy. Under each Domain, is a list of Kingdoms where this beast needs to be placed. Our creature is in the Domain: Eukarya, so we can ignore the other Domains. Under Eukarya, there are six different groups where are Kalla-Wagga may sit; Archaea, Bacteria, Protista, Plantae (seaweeds, land plants), Fungi (mushrooms, yeast, moulds, etc), Animalia. (There have been debates about the number of Kingdoms mainly focusing on the smaller microscopic organisms. Six Kingdoms appears to be the current consensus.) This is another easy one; our Kalla-Wagga isn’t a microbe, or mushroom, or shrub; it is an animal. So we have the Kalla-Wagga in the Domain: Eukarya; Kingdom: Animalia. This classification business isn’t so tricky after all!

The next dividing group is the Phylum. There are 35 different Phyla under the Kingdom Animalia (the plural of Phylum is Phyla). So where are we placing our Kalla-Wagga? Well, fifteen of these are Phyla for different types of worms, and our new creature definitely isn’t a worm! There are a lot of groups for jelly like creatures, including jellyfish and the Kalla-Wagga clearly does not share any of the features of these Phyla. There is a Phylum for sea mats (Bryozoa), sponges (Porifera), water bears (Tardigrada) and several others grouping creatures which share similar body features which the Kalla-Wagga clearly doesn’t sit. Another group, the Arthropoda could be a good candidate; everything in this group has jointed legs and skeletons on the outside of their bodies, like crabs, spiders, flies, and beetles. We look at our Kalla-Wagga. No skeleton on the outside. The way he is curved you can see his spine pressing out in his back. He has a backbone! Now we know which Phylum he belongs to; Chordata. All animals with a backbone (vertebrates) are placed under the Phylum Chordata.

Ace. Our quest for classifying the Kalla-Wagga goes well. Just a few more steps until we can name this creature. From here on in there are different groups bunching together animals with more and more similarities. We will need to look at a few more groups; Class, Subclass, Order, Family, Genus and species. Thrown above and below the first four of these main groups is a big mix of other groups; Infraclasses, Clades, Superorders, Grandorders, or Infraorders. For the purpose of classifying the Kalla-Wagga we will focus on the main groups highlighted in bold.

The next group down is the Class. There are seven Classes where our big-eared friend may sit; Aves (birds), Reptilia (reptiles), Mammalia (hairy, sweaty, lactating mammals), Amphibia (frogs, newts and salamanders), Agnatha (lampreys), Chondrichthyes (sharks, skates and rays), and Osteichthyes (boney fish). We know the Kalla-Wagga is not a fish, so we can discard the Agnatha, the Chondrichthyes, and the Osteichthyes. He doesn’t have wings or feathers, so would not sit well in the Class Aves. He has hair covering his body, different shaped teeth, and nipples; these are all features shared by animals in the Class Mammalia.

All mammals share the same features; hair, lactate milk to their young, three ear bones and an articulated jaw.  Image from Wiki: George Shuklin (http://en.wikipedia.org/wiki/File:%D0%9C%D1%8B%D1%88%D1%8C_2.jpg)

All mammals share the same features; hair, lactate milk to their young, three ear bones and an articulated jaw.
Image from here.

Fantastic! Our Kalla-Wagga is a mammal. Here we can finesse it out even more! The next group is Subclass and the Mammalia is divided into three Subclasses; the Prototheria (monotremes; egg laying mammals), the Marsupialia (the young are carried in a pouch), and the Placentalia (the young are nourished by a placenta before birth). (Again, this can get very complex with Infraclasses, Clades and others. The important split for this is the three groups just mentioned.) Sha’re has told us that the Kalla-Wagga is born live and they feed from the mothers breast, not in a pouch; so these mammals belong in the Subclass group, Placentalia.

We are doing very well indeed. And just a few more steps until we reach the end! So far, we have worked out that our shiny arsed friend sits in the Domain: Eukarya; Kingdom: Animalia; Phylum: Chordata; Class: Mammalia; Subclass: Placentalia.

The next group we need to work out is the Order. Under Placentalia, there are 12 different Orders. I quite like the Order Pilosa because this has a cool translation; the ‘hairy ones’. But the Pilosa contains animals which contain very small teeth, including armadillos and sloths; we know the Kalla-Wagga has a lot of fairly big teeth, so doesn’t sit in this group. Looking at the features of the other Orders helps us work out where Sh’are’s demon will fit. Our animal does not have hooves, like a horse or camel, so we won’t place it in the Orders Perissodactyls or Artiodactyls, respectively. Neither does the Kalla-Wagga have winged hands, so we won’t place him in the Order Chiroptera (bats), or curved incisor teeth, so he’s not in the Order Rodentia (rodents). The Kalla-Wagga is not adapted for ocean life, like a whale or a dolphin, so doesn’t belong in the Order Cetacea, nor does he belong in the Order Sirenia, because he doesn’t have flippers and a tail that is shaped like a paddle (like a dugong, or a manatee). He’s not an elephant (Order Proboscidea), nor a rabbit (Order Lagomorpha), nor a bear or lion (Order Carnivora). We have filtered it down to the last Order, the Primates; and the Kalla-Wagga shares the main characteristics of this group including, fingernails and toenails instead of claws, grasping feet and hands, eye sockets tat face forwards, and very good vision.

All Primates share common features, including  Image from Wiki (http://en.wikipedia.org/wiki/File:Hamadryas_Baboon.jpg)

All Primates share common features, including fingernails and toenails instead of claws, grasping hands and feet, and eye sockets facing forwards. 
Image from here.

Almost there! Now we have to find out which Family this creature belongs. There are 16 Families in the Order Primates. Although tempting, because of the rather cool monkey names, we won’t put him in the Family Atelidae (which includes the amazing woolly spider monkeys, woolly monkeys, howler monkeys and spider monkeys). One key features helps us dismiss other Families; the Kalla-Wagga has no tail. There are two Families which group together Primates without tails; the Hylobatidae (gibbons) and the Hominidae (chimpanzees, gorillas, orang-utans, and humans). All the other Families in this Order have tails. The Hylobatidae (gibbons) share anatomical details that are more similar to monkeys and they move by swinging their arms through the trees, with their wrist is made up of a ball and socket joint. The Kalla-Wagga shares more features with chimpanzees and gorillas than gibbons, so we can place him in the Family Hominidae.

We are now at the penultimate stage of finding a name for the strange beast we found in the jungle that night. We reach the Genus (plural genera). This is the group that holds all the species below it; some genera will only have one group of organisms (a species) below it, such as the platypus; whereas some genera may contain many species such as the Genus Panthera includes the species of lion, tiger, jaguar, leopard, and snow leopard. In the Family Hominidae, there are 4 different genera; Pongo (orang-utans – 2 species); Pan (chimpanzees – 2 species); Gorilla (gorillas – 2 species); and Homo (humans – 1 species).

It will be useful for us to look at the distinguishing features and characteristics that make these 4 genera separate from one another. The species in the Genus Pongo share red/brown coloured hair, cheek pads (which the males use for mating) and are very efficient swingers through the trees. The beautiful Genus Gorilla are ground dwelling hominine which walk on their knuckles and their lower jaws stick out a lot more than their maxilla (the upper palate in the mouth). Chimpanzees (Pan) have arms which are longer than their legs, walk on their knuckles, and have small brains (between 280 – 500 cubic centimetres). The species in the Genus Pan also have broader soles on their feet, and shorter toes than orang-utans. The one living species in the Genus Homo walks upright on two legs, and has a large brain (over 600 cubic centimetres). Our punk rocker ape shares a few similarities with each of these four genera, but not enough to place him comfortably in one of them. So we have a creature from a Genus (and species) which doesn’t yet exist!

(The details defining which organism belongs in which Genus is much more detailed than described above. There are detailed anatomical measurements which place an animal (or plant) comfortably in a certain Genus. For example, detailed measurements of the skeleton of individual species provide a range of measurements in that species; generally those bones within that range will be for that species. A thousand (or more) individuals in a species will be measured and analysed providing a benchmark of ranges for that species. The majority of the time palaeontologists studying fossils often only have one bone to work from, and here the skeletal analysis is vital. The shape, curvature, length and girth of that individual bone can be enough to say what species it belonged to, or if they have discovered a new species.)

This is very exciting. The Kalla-Wagga has no Genus. We can name a new Genus for him to fit into. We will have to write a very detailed scientific paper comparing him to the other Primates, and in particular the other species in the Hominidae. I am tempted to name the creature Suntfaceiem after first seeing it’s bizarre rear end; literal translation “arse face”. I refrain from this ever so slightly witty Latin name and decide to call the Genus after our wonderful guide; Genus Sharepithicus, which translates to ‘Sha’re’s ape’.

As with the Genus, this is a new species of animal. A species is an individual group of organisms that can mate and produce fertile offspring. The group of individuals is distinct enough for other members of the Genus to be named as an individual species. For some creatures this is visually clear, such as the lions and tigers both belong to the same Genus but are different species.  For others, such as beetles and flies, it may be more subtle differences which defines the species, such as the shape of the genitalia.

Our Kalla-Wagga, propped up in his oversized jam jar filled to the top with formalin is the type specimen; the specimen that defines this species. And of course there are rules to naming a new species. I can’t name it after myself, but as you saw with the Genus I can name it after someone else. I am allowed to name it, as I am scientifically describing it in a scientific journal. I will need to inform the International Committee for Zoological or Botanical Nomenclature of the new Genus and species name I propose – they check that it hasn’t been used before.

I am tempted to name it after one of the greatest people in science, ever; Mr Thomas Henry Huxley. I think about adding the species name huxleyii to the new genus. (When writing the Genus and species name it is written in italics. If writing by hand then it should be underlined. The Genus always starts with a capital, and the species is always in lower case.) The publication has the new species in the title: “A new nocturnal Primate (Family Hominidae; Sharepithicus eleanorii) from the Congo Basin and it’s rather unique mating ritual”. I name it after my wife. (Best to be in the good books.) It’s a ruddy good job I didn’t name this beast Suntfaciem eleanorii – ‘arse faced Eleanor’ is not the way to immortalise one’s beloved.

We have done it! We have gone through all the different groups and even named a new species! Here are a few familiar creatures and how their taxonomy is similar higher up, and then splits lower down;

Domain                 

Eukaryka

Eukaryka

Eukaryka

Eukaryka

Kingdom              

Animalia

Animalia

Animalia

Animalia

Phylum                  

Chordata

Arthropoda

Chordata

Chordata

Class                      

Mammalia

Insecta

Amphibia

Mammalia

Subclass              

Placentalia

Placentalia

Order                    

Primates

Lepidoptera

Anura

Primates

Family                  

Hominidae

Sphingidae

Ranidae

Hominidae

Genus + species   

Homo sapiens

Laothoe populi

Rana temporaria

Sharepithicus eleanorii

(Human)

(Poplar Hawk Moth)

(Common Frog)

(Kalla-Wagga)

 

What a wonderful hypothetical creature! (Hardcore Stargate SG-1 fans may have noticed Dr Jackson’s lost love.) There is no reason that a creature like this has never existed or won’t exist one day in the future. But for today (as far as I know) the Kalla-Wagga doesn’t exist. It is entirely plausible. Sexual selection has created a wonderful variety of extreme forms from the beautiful mating rituals of birds of paradise, to the delightfully eccentric noses of the proboscis monkeys.

As well as being a clear simple way of organising all life on the planet, the beauty of classification is how it shows how closely animals are related. All mammals share a common ancestor which diverged from reptiles around 300 million years ago. You won’t find a mouse in the Class Insecta. As you work your way down the different groups, animals are more closely related; all Primates are more closely related to each other than they are to kangaroos. Genetics is showing these relationships in even more detail, and as a result some organisms have had to be moved from one Genus to another.

The ‘Kalla-Wagga’ could have easily have been a fish, or an insect, or a salamander. To identify any creature you like, you would go through similar steps and look at the features that determine each of the groups until you reach the end. The process and long words in taxonomy can be confusing and sometimes put people off. But now you know a little more you can look at any animal or plant and try and identify it as it’s your own enigmatic and beautiful Kalla-Wagga. Think of taxonomy as a Kalla-Wagga slapping its own arse; sexy, beautiful, elegant and effortless (and apparently painless).

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Linnaeus and the Breast

Humans have questioned where we belong in the natural world for centuries. Some still ponder today. Charles Darwin skimmed over the subject very briefly in his wonderful masterpiece On the Origin of Species outlining his theory of evolution through natural selection. Tantalisingly Darwin writes a one liner where humans may fit in; “Light will be thrown on the origin of man and his history”. Darwin’s close friend and supporter, Thomas Huxley, examines in detail the human species compared to other animals in his own masterpiece Man’s Place in Nature (1863). Typical of Huxley’s work, he provides clear and logical comparisons to other species, focusing on apes in particular. To introduce his comparison with animals, always eloquent, Huxley writes;

“The question of questions for mankind – the problem which underlines all others, and is more deeply interesting than any other – is the ascertainment of the place which Man occupies in nature.”

Huxley, Man’s Place in Nature. 1898 Edition. pg 77.

The famous image from Huxley's Man's Place in Nature demonstrating the similarities of the anatomy of the great apes.  (Image from

The famous image from Huxley’s Man’s Place in Nature demonstrating the similarities of the anatomy of the great apes.
(Image from here)

The answer for Huxley’s ‘question of questions’ is surprisingly laid bare in the classification of animals developed 150 years earlier. (Classification is simply organising life. All organisms on the planet are divided into a number of groups which place those with similar features into the same group.*) Of course Huxley talks about classification in Man’s Place in Nature clearly showing us how animals are organised and where humans sit in this classification.

The beginnings of the classification system we use today was developed in the 1700s by a Swedish chap who had a little fondness of breasts. Our story begins long before then, in the heat of the bustling city of Athens where the temples were full, the amphitheatres were packed and the wine filled amphorae were passed round carefree every evening.

Aristotle (384-322BC), the famous Greek philosopher, taught many noble men (including Alexander the Great), and his writings covered a ridiculously diverse range of subjects including politics, music, ethics, poetry and biology.

The great thinker looked at animals and plants and grouped them based on his own observations (looking at the way they move, a little bit of reproduction, and what they are made up of). For the first time, his work grouped animals together based on their similarities. He split the first group into two; ‘Blooded animals’ (basically animals with a backbone; the vertebrates) and ‘Bloodless animals’ (those animals without a backbone; the invertebrates). Aristotle broke the next categories down even further; life bearing (humans and mammals) and egg bearing (birds and fish). The classification didn’t stop there: it went on for some more levels each time grouping animals with similar features so that each time the groups contained less and less animals until it ended up with the individual. The old scholar used his groupings to show a ladder of the simplest organisms moving upwards to the highest, his ‘Great Chain of Being’. Much of this work set the basis for subsequent classification of the natural world.

A lovely marble bust of Aristotle showing rather chiselled features.

A lovely marble bust of Aristotle showing rather chiselled features. (Image from here)

Aristotle’s work on animals and plants stuck around for around 2000 years, before there was a renaissance in looking at the life around us. This mainly began with new attempts at classifying plants because of their important uses in medicines. The Italian botanist, with a rather well trimmed beard, Andrea Casalpino (1519 – 1603) was one of the first to look at the features of plants and use the similarities to classify them. He wrote a somewhat large and, to many people, fairly quite an un-thrilling piece of work describing and classifying over 1500 species based on the structures of the seeds.

Soon after there was an obsession to classify more. Another botanist, this time from Switzerland and a much more elaborate beard, Gaspard (or Caspar) Bauhin (1510-1624) wrote an enormous book on plants. Titled Pinat theatre botanici (Illustrated exposition of Plants), he describes and classifies over 6000 species. Regardless of the slightly limited readership, the wonderful thing about this book was that Bauhin grouped similar plants together, and he introduced the method of using genus and species in his classification; plants which Bauhin thought were similar were placed in the same genus and then each different individual plant was then given their own species name. This method of naming organisms using a genus and species is still used today.

These passionate and mildly obsessed bearded gentlemen had begun to try to arrange life by giving them Latin names. Over the years, there were several attempts with a variety of different groups added and moved around. John Ray (1627 – 1705) was an (unbearded) English man who attempted to classify a huge number of species (over 18,000 plants in one publication!). Ray’s system was thorough but he appeared to combine different characters of different plants in his ‘organising’.

With such a huge variety of different ways in organising life and different names being given to the same plant, there needed to be a standard that would be used the world over. Enter a man who was rather fond of breasts.

Carolus Linnaeus, also known as Carl von Linné, (1707-1778) was a clean shaven Swedish naturalist who gave lectures in botany at Uppalsa University. He had a pure lust for studying as much as he could about the natural world. Linnaeus developed his Systema Naturae (System of Nature) in 1735 as a twelve page list of organising the plants, animals and minerals he knew. His cravings were not satisfied with this work. For the next 31 years he had developed several editions resulting in his monstrous 12th Edition in which he organised and classified over 12,000 different species. All the animals and plants in his Systema Naturae were given binomial names (genus and species) and this set the precedence for future work on naming life. Linnaeus’s system has been widened, adapted and changed over time, but the basic idea is still the same.

Carolus Linnaeus (or Carl von Linné (1707-1778). A Sweedsih naturalist who was well kept and developed the system of classification we use today.

Carolus Linnaeus (or Carl von Linné (1707-1778). A Sweedsih naturalist who was well kept and developed the system of classification we use today. (Image from here)

It is the famous 10th Edition where we get a first glimpse of the breast. Over 2000 years earlier, Aristotle had grouped all animals on four legs as Quadrupedia (including mammals, most reptiles and a lot of amphibians). Makes sense, as they all have four limbs. There were a few problems with the term Quadrupedia which naturalists were not too keen on; for example, manatees only have two ‘hands’, chimpanzees have four ‘hands’, and humans have two feet and two hands. But Linnaeus sorted this out in a little more detail. Along with some classes from the old philosopher, he developed some new ones for his classification resulting in six classes; Mammalia (mammals), Aves (birds), Amphibia (reptiles and amphibians), Pisces (fish), Insecta (insects and arachnids) and Vermes (worms). This allowed for large groups which shared similar features to be grouped in these classes. For example all species of Owls were placed in the same Order (Strix), and this Order was grouped with all other Orders of birds under the Class Aves.

Wonderful. And the link to breasts is in there too. But this will need a little explaining, as it may appear that I have some weird geeky fetish to taxonomy where systematics is the nipple that I enjoy tweaking. Although many of us do get excited about fantastic science, it is not really a fetish. Not really. I don’t have a room fully of pictures of taxonomic trees on my walls in front of a lovely old oak desk covered in pinned insects, study skins and a delightfully old microscope. One day perhaps I will. But for now, my little ‘office’ under the stairs will do.

Linnaeus unveiled the breast in the new class he developed; Mammalia; literally meaning ‘of the breast’. He could have used a different term for this group of animals because there are six little features that you can look at in any animal anywhere that determines whether or not it is a mammal;

  1. An articulated jaw. All mammals have one bone in their lower jaws, the dentary (two dentary bones on the left and right side, which are fused together at the chin). Reptiles have three bones in their lower jaws.
  2. Three ear bones. The lovely little incus, mallus and stapes are the smallest bones in the human body. These three tiny, beautifully shaped bones were once three bones in an early reptilian ancestors head. Three bones, the quadrate, articular and angular in one group of very early reptiles shrank, moved, and became vital in amplifying sound in the animal. This took a long time, and many generations and mutations; each change being useful and passed onto the next generation. We know this because otherwise we wouldn’t laugh and weep at a magnificent performance of the beautiful Madame Butterfly.
  3. Mammary gland. The milk producing glands which are functional in the females and only for a short period of time. This can be with the help of a nipple, or like the platypus and spiny anteater lactating milk on your chest is enough for the little ones to lap up.
  4. The aortic arch (a main artery in the heart) bends to the left. This is a very efficient way of transporting oxygen rich blood round the body as the heart pumps.
  5. Cheek teeth with divided roots. All mammals have the teeth at the back of their mouths (the molars) which have at least two roots holding the tooth into the jaw. Mammal teeth vary for different uses; the flat incisors at the front for nipping grass or flesh; the sharp canines for piercing prey or fighting other males; the pointy pre-molars for slicing or grinding; and the back molars to really slice or grind. Fish, reptiles and amphibians only have the same type of tooth throughout their mouths and one root.
  6. Hair or fur. Mammals are the only animals that have ‘true’ hair which covers their bodies at some point in their lives. The hair grows from skin cells, called follicles, with the little protein keratin.

The term Mammalia derives from the Latin word mammae, referring to the breast or nipple as appose to the actual milk producing glands (the mammary glands). It is interesting that Linnaeus focused on a female feature to name this large group of animals. Some animals in this Class do not have breasts or nipples; such as the wonderfully enigmatic platypus and bizarre quirky spiny anteaters, which are the only living members of the egg laying mammals, the Monotremes. These creatures have all the features of a mammal (three ear bones, single jaw bone, hair, produce milk through mammary glands). But they lay eggs. And they don’t have nipples. (The Monotremes secrete milk from their mammary glands, which the youngsters lavishly lap up.) Because of the features they share with all other mammals, apart from laying eggs, these beautiful creatures do belong to the Class Mammalia.

So really the nipple or breast isn’t actually a defining diagnostic feature of Mammalia. For those mammals that do have nipples, generally both the females and males have them. This is simply because the nipples form in the developing foetus before the sex is developed; for a while in the womb the little developing animal is sexless. (There are exceptions where some male mammals don’t have nipples, for example, horses and some rat species). The true feature of a mammal is not whether it has a nipple or breast, but it is an animal where the females produce milk to nourish their young.

As a little aside, it is delightfully curious that only our species uses the breast for enjoyment during nights of passion. Many women, and men, find the nipple and the surrounding area to be an extremely sensitive and pleasurable part of the body. The amazing and complex evolution of the sex lives of our species is for a future post, but the breast clearly played an enchanting role in our species enjoying and prolonging the sex for as long as we do.

Back to Linnaeus and the breast. Why would he have focused on the breast? He could have easily chosen another term, such as Pilosa (the hairy ones), Aurecaviga (the hollow eared ones), Lactentia (the lactating ones) or Sugentia (the suckling ones), Tresauremos (those with three ear bones), Unamaxillia (one jawed ones). By naming the Class of hairy lactating creatures Mammalia, he created a simple link to include one certain species within his classification; us.

The 10th Edition which saw the introduction of the new term Mammalia, also saw the first time of including humans within the System of Nature; he gave humans the scientific name Homo sapiens. By giving humans a scientific name and including them within his classification, Linnaeus had linked humans with the animal kingdom. Humans were placed along with apes, monkeys and sloths in the Order Primates. (Sloths are no longer within the Primates, but are in a new Order Pilosa along with anteaters.) Of course, there was uproar! Humans in the same group as monkeys!! Oh, to be a fly on the wall as the great scientific folk read this for the first time! But Linnaeus was clever. He showed there was no way out from classifying humans along with other animals; humans share many of the same features as all mammals. One of these features which there was certainly no denying was the breast.

Historically, breast feeding has been seen as linking humans closer to the animal kingdom quite simply because other animals do it, resulting in women seen to be closer to the animals than men. Aristotle noted how women gave birth to live young and nursed their young, just like many other animals. Confused by bodily functions, many people thought that menstruation and lactation were linked; Aristotle believed that the menstrual fluid transformed into the fluid for nursing the young after giving birth. This complete lack of understanding of biology is what we would see today as completely bonkers. Amazingly until the mid-1700s Aristotle’s view on things was believed to be true (that’s 2000 years of silence in the study of science!).

The wonderfully large nipples (or teats) of a female goat with her young close by. The nipples are very large so the baby goat can get easy access. (Image from Wiki: http://en.wikipedia.org/wiki/File:Goat_family.jpg . Image Taken by Fir0002/Flagstaffotos)

The wonderfully large nipples (or teats) of a female goat with her young close by. The nipples are very large so the baby goat can get easy access.
(Image from here)

The choice of the term Mammalia is interesting because the names of all the other groups focus on features shared by all animals in that group. For example, the Phylum Arthropoda means ‘jointed legs’, which all animals (both male and female) in this group have. The Class Amphibia means ‘both lives’ as all these slimy creatures in this group live in and out of water. Mammalia however, focuses on the female of the species. By giving the Class the name Mammalia automatically shows that humans are no different and fit within the classification.

Mr Linnaeus probably thought about breasts for quite some time with this strategic move. With the breast proudly exposed as the defining trait for the group, humans could be included. And here, he was very clever again. He named our species Homo sapiens meaning ‘man of wisdom’ which was a very proud and masculine name. Linnaeus made sure the breast and the woman linked with other animals, and ‘man’ stood alone. Like many in the 1700s, and even 1800s, he still thought that ‘man’ was special, one of God’s greatest creations (Linnaeus himself was a Creationist). So humans fitted in his classification, but were separated from the ‘lower animals’ by the species name he gave. Very clever.

The breast: one defining feature to link humans with the rest of the animal kingdom. Although Huxley’s ‘question of questions’ wouldn’t be asked for another 150 years, Linnaeus had already began to answer it. Linnaeus had wanted to satisfy his lust by organising nature and by doing so he grouped together animals with similar features (ie. animals that were closely related). It was never his intention to demonstrate any evolutionary relationship. His classification however beautifully illustrates the wonderfully diverse tree of life and how all organisms reveal clues to their evolutionary past.

This Class of animals, the beautiful and varied group of mammals, is absolutely extraordinary! One feature in particular is a true marvel of the natural world; sweat glands in one particular part of the body have been modified to produce milk and secrete it through contractions of ducts. Truly remarkable! Only mammals can do this. And this is the real beauty of these creatures. The dinosaurs didn’t breast feed their young; mammals did.  

The Class Mammalia does not demonstrate that women are closer to animals than men – this is an ancient idea that should have faded into dust. Quite the contrary. It shows the importance of females without which the Class would not exist. This is the reason the breast proudly sits so high up, defining this Class of fury, sweaty animals. And quite rightly so. One of the most beautiful features that has evolved in nature has now been immortalised as the defining feature of a very diverse and amazing group of animals we belong to; the mammals.

References;

Huxley, T. H. 1898. Man’s Place in Nature and other Anthropological Essays. New York. D. Appleton and Company.

Schiebinger, L. 1993. Why mammals are called mammals: gender politics in Eightieth-Century Natural History. The American Historical Review. Vol. 98. No 2. pp.382-411.

 

*The world of organisms is divided into a number of groups which place those with similar features into the same group. All animals belong to the Kingdom Animalia. These are then split into different Phylum (for example, those with a backbone (vertebrates) are placed in the Phylum Chordata). This Phylum is divided into 6 different Classes; all the birds for example are in the Class Aves, and all the mammals in put in the Class Mammalia. Each Class is then divided further with a number of Orders; all bats are in the Order Chiroptera and all cats, dogs, bears, walruses, seals, racoons and skunks are in the Order Carnivora. This is not the end! There is another divide under Order, the Family; this is where the groups become more closed and specialised. For example, all the species of kangaroos are in the Family Macropodidae and al the chimps, gorillas, orang-utans and humans are in the Family Hominidae. The penultimate group level is the Genus. Here there are fewer organisms in this group, sometimes there can be on animal in this group, or sometimes ten. The final group is the species. This is where the individual animal is named, for example all humans belong to the Genus and species Homo sapiens where as all blue tits belong to the Genus and species Cyanistes caeruleus.

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