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Diversity of Life B > Week 20 > Flashcards

Week 20 Flashcards

1
Q

How are Barn owls (Tyto alba) highly adapted?

A

are highly adapted for preying on small mammals.

  • Concave face collects sound
  • Prey swallowed whole
  • Feathers adapted for silent flight
  • Broad wings give greater lift.
  • Sensitive eyesight and hearing
  • Long legs and sharp talons
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2
Q

Why are owl pellets produced?

A

Pellets are produced because owls eat their prey whole and then regurgitate the undigested bones, teeth, and fur. These can then be used to identify the owl’s prey.

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3
Q

Why is it relatively easy to investigate the diet of owls?

A

They produce pellets of regurgitated fur and bones.

Investigating the diet of animals can be difficult. Owl pellets provide an easy to dissect record of the prey animals eaten by an owl.

Fur, bones, teeth, nails, feathers may all be idenitified within owl pellets.

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4
Q

Referring to the scientific paper on Barn Owl diet by Love et al (2000), which of the following is one of their main findings?

A

Diversity of Barn Owl diet increased between 1974 and 1997.

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5
Q

In the methods for this practical you are asked to estimate prey biomass for the owl pellets (see the instructions).

Which two methods will you use to estimate biomass?

A

Calculate bird biomass from humerus length.

Use representative biomasses of mammal prey items.

In this practical representative biomass of small mammals will be multiplied by the minimum number of individuals for each species.

Secondly, for bird species where any humerus bones has been identified, biomass can be calculated using the equation

Log mass (g)= (2.4221 x log humerus length (mm)) - 3.8027

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6
Q

From the data you collect in the practical in what format have you been asked to present your results?

A

One pie chart on prey number, and one pie chart on prey biomass.

The quantitative data you collect on owl diet will be used to look at the proportion of the diet made up of different mammals.

A pie chart is appropriate for comparing proportions.

Two pie charts are required because you will look at both numbers of individuals and biomass.

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7
Q

Today, biologists have identified about 5,000 species of which of the following?

A

Mammals

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8
Q

True or false: Whales have hair.

A

Whales are mammals and have fur.

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9
Q

Which of the following has allowed mammals to conserve heat and move into colder climates?

A

Hair

Fur

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10
Q

The presence of hair and fur in mammals functions to conserve body ______
, and to ______
the animal against its background. Whiskers can serve as a ______
structure, and the quills of a porcupine can defend it against predators.

A

Blank 1: heat
Blank 2: camouflage
Blank 3: sensory

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11
Q

The main function of the mammary glands in female mammals is to produce and secrete _____
, a protein and fat rich liquid that nourishes newborn animals.

A

Blank 1: milk

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12
Q

Roughly how many species of mammals do we recognize at present?

A

5,000

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13
Q

Which of the following are features of mammals that support their high metabolic rate (needed to maintain endothermy)?

A

Efficient respiration provided by the diaphragm

Four chambered heart

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14
Q

Mammals are distinguished from other vertebrates because all mammals have _____ , although some have more than others.

A

Blank 1: hair or fur

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15
Q

Which type of teeth are not found in deer?

A

Canines

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16
Q

The evolution of _____
in mammals has allowed mammals to conserve heat and adapt to living in _____
climates.

A

Blank 1: hair or fur

Blank 2: cold, colder, cool, or cooler

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17
Q

_____ are composed of keratin and protect the toes of horses and sheep.

A

hooves

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18
Q

Which of the following are functions of hair in mammals?

A

Provides warmth

Sensory structures

Camouflage

Defensive mechanism against predators

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19
Q

All females mammals possess ______

glands, which secrete a protein and fat rich liquid that can nourish their newborns.

A

mammary

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20
Q

The bat wing is a leathery membrane of skin and muscle that is stretched over how many of its fingers?

A

4

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21
Q

In order to support the high metabolic rate needed for endothermy, mammals have an efficient ______
-chambered heart and a specialized muscle, the _____, which allows for efficient respiration.

A

Blank 1: four or 4

Blank 2: diaphragm

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22
Q

Which of the following are used by bats to navigate in the dark?

A

Sound

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23
Q

Which type of teeth in dogs are well suited for biting and holding prey?

A

Canines

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24
Q

Mammals first evolved about _____

MYA.

A

Blank 1: 220

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25
Q

Which of the following are composed of keratin?

A

Claws

Fingernails

Hooves

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26
Q

Which are likely characteristics of the first mammals?

A

Nocturnal

Insectivorous

Tree climbing

Small

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27
Q

_____ are the only mammals capable of sustained flight.

A

Bats

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28
Q

Bats use ______ to locate food in dark environments.

A

Blank 1: echolocation, hearing, or sound

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29
Q

Which of the following was the most primitive group of early mammals?

A

Prototheria

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30
Q

Which of the following accurately describes when mammals first evolved?

A

220 million years ago

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31
Q

Which of the following are a part of the subclass Theria?

A

Placental mammals

Marsupials

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32
Q

Early mammals lived in ____ and ate ______. They had large _____
sockets, and a single lower _____.

A

Blank 1: trees
Blank 2: insects
Blank 3: eye
Blank 4: jaw or jawbone

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33
Q

Currently, the only living monotremes are the duck-billed _____ and two species of ____.

A

platypus

echidna

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34
Q

Although monotremes, such as the duck billed platypus, are mammals, they retain many ______
features; for example, they lay eggs and have a cloaca.

A

Blank 1: reptile or reptilian

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35
Q

The most primitive group of early mammals was ______ which mostly consisted of small, shrewlike animals that laid ______ like their synapsid ancestors.

A

Blank 1: Prototheria

Blank 2: eggs

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36
Q

What are the features of these three mammal group?

1- Monotremes
2-Marsupials
3-Placental

A

1- Mammals that lay eggs.
2- Mammals that carry their young in a pouch.
3- Mammals that nourish their embryos using a specialized organ.

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37
Q

The mammalian subclass Theria consists of ______
mammals. The group includes both placental mammals and marsupials, but excludes the ______
because they lay eggs.

A

Blank 1: viviparous or live-bearing

Blank 2: monotremes

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38
Q

Platypus and echidnas are both found in

A

Blank 1: Australia

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39
Q

Which of the following are extant species of monotreme mammals?

A

Long-nosed echidna

Short-nosed echidna

Duck-billed platypus

40
Q

The fertilized egg of a marsupial is surrounded by by chorion and amniotic membranes but there is no ______ ______ around the egg as there are in monotremes.

A

Blank 1: egg

Blank 2: shell

41
Q

Which are common characteristics between monotreme mammals, like the platypus, and reptiles?

A

Cloaca

Shoulder structure

Oviparous

42
Q

Which of the following are among the groups of living mammals?

A

Marsupials

Monotremes

Placental mammals

43
Q

Which of the following animals of Australia have electroreceptors in their bill so that they can detect the electrical discharges produced by muscle contractions of their prey, thereby locating the prey easier.

A

Platypus

Echidnas

44
Q

Marsupials continue embryonic development by attaching to a ______
gland in the mother’s pouch

A

Blank 1: mammary

45
Q

How many mammals are in the class?

A

Numbers of orders within Class Mammalia vary somewhat too, but we’re going to go with 27.
Of these 27 we’re going to consider most of the 19 placental orders as well have a quick look at the remaining 8, one of which belongs to the monotreme clade and the remaining 7 belong to the marsupial clade.
So we’ve got 1 class, 2 subclasses, 27 orders, numerous families and approximately 6,500 species of mammal.
Amazingly, about 40% are rodents and about 1/5th are bats.
Mammalian phylogeny undergoing radical changes.
27 Orders (1 prototherian, 7 marsupial, 19 placental).
6,513 species described at recent count (2021).
2,590 rodents, 1,430 bat species.

46
Q

Mammae =

Mammillae =

A

Mammae = mammary glands = milk production. Modified sweat glands.
Mammillae = nipple/teat = milk delivery
Generally twice as many nipples as average litter size

47
Q

What are some key features of mammals?

A
  • Teeth are replaced once or never, not continuously.
  • Prismatic enamel on teeth.
  • 2 occipital condyles where the skull meets the topmost neck vertebra.
  • Only one ancestor.
48
Q

What are the occipital condyle in mammals and why is it better to have two?

A

Well they are these two knob-like protrusions on the back of the skull which articulate with the top of the spine.
Having two condyles rather than one was good news as this reduced tension on the spinal cord when the head is moved vertically and also allowed for finer control of head movements although reduced lateral movement.

49
Q

What is one of the key features of the amniotes?

A

was that they evolved to produce cleidoic, or shelled, eggs (compared with frogspawn). This shell was a key adaptation which allowed for successful reproduction on land.

50
Q

What does the phylogenic tree tell us about our ancestral amniotes?

A

We have our ancestral amniotes at the root of the tree- we get the reptiles branching off and the only anapsids alive are the turtles. We have another clade of diapsids and these include everything from crocodiles to now extinct pterosaurs. Some of these dinosaur clades include the closest relatives of birds today also plesiosaurs, ichthyosaurs and some of these more unusual reptiles, lizards, snakes and Tuataras and the only branch on the synapsids here concerns mammals.

51
Q

What were the first species to show mammal like features?

A

A group of synapsids known as pelycosaurs were the first beasts to show mammal-like features, some 320 mya, and these are shown in the fossilised remains of a creature named Dimetrodon.

52
Q

When did the dinosaurs become successful?

A

It was later during the Triassic that the dinosaurs became extremely successful and then during the Jurassic and Cretaceous periods (200-65 mya) they eclipsed the therapsids and almost out competed them into extinction. Indeed many of the other synapsid lineages did go extinct during that time.

53
Q

How have mammals become more efficient at moving?

A

This rotation of the limbs by 90 degrees and other derived changes to pelvic and pectoral girdles means that mammals today are able to move more efficiently.

54
Q

What are the benefits of Therapsids having limbs beneath their body?

A

Therapsids have quite a number of mammal-like characteristics and one of these is they now carry their limbs beneath their body. This gives them a much more rapid form of locomotion. It could be better, for example for being predators or for even if you’re a prey species escaping from predators by having more rapid locomotion.

55
Q

What are the basic properties of the first mammals?

A

•Separated from therapsids in late Triassic, maybe about 240 Mya.
•Probably largely nocturnal and insectivorous – niche not available to reptiles.
probably occupying a niche unavailable to ectothermic reptiles.

56
Q

What are the benefits of comparing modern day mammal teeth to extinct fossils?

A

By comparing modern day mammal teeth to extinct fossils we can paint a picture of what some of the Mesozoic mammals would have fed on and use this to work out ecomorphologies, how their physical adaptations relate to their ecological role.
During the past 30 years many more fossils have been discovered which lead us to believe that rather than all early mammals having generalised feeding habits there was actually a wide array of specialisation, as we see today, long before the extinction of the dinosaurs.

57
Q

What is present in the subclass Prototheria?

A

Order Monotremata

Most primitive mammals alive today, few fossils.
Continents broke up in the late Mesozoic era, ancestors of monotremes restricted to the southern supercontinent, Gondwana.

58
Q

Why is there uncertainty on the origin of the monotremes?

A 
Within the subclass prototheria there is only one surviving order – the monotremes.
There is lots of debate about the origin of the monotremes but one idea suggests they evolved from creatures called Australosphenidans.

Why the uncertainty? Well there are few species alive today and the fossil record isn’t as good as palaeontologists would like it to be so we have little evidence to go on.
However, most agree monotremes are the most primitive lineage of mammals alive today, still retaining many of ancestral traits – although they are by no means less complex.
During the cretaceous period the supercontinent Pangaea split into Laurasia in the north and Gondwana in the south. Looking at the distribution of monotremes alive today, it seems likely that the ancestors of monotremes were restricted to Gondwana in the south.

59
Q

What are the key features of the order monotremata?

A

The young hatch out of their eggs after about 10 days and are then fed on milk.
monotremes lack teats/nipples and so the infants have to lap up the milk which oozes out of mammary glands and onto tufts of hair.
Other key features of extant monotremes: they lack teeth (have horny plates instead) and have venom glands.
There are only 5 species of monotreme alive today - 1 platypus and 4 echidnas

60
Q

Which is the most important staple?

A

maize

61
Q

Which parts are the most important source of dietary calories?

A

seeds

or other storage organs

62
Q

Which part of plants are the best source of oil?

A

seed
fruit
storage organs

63
Q

Why do plants store oils?

A

energy storage

64
Q

Which plant parts are the best places for protein?

A

nuts
seeds
storage organs

65
Q

When were most of our crops domesticated?

A

10,000 years ago

66
Q

Which plant family is a good source of protein?

A

legumes- bean family

Fabaceae

67
Q

Which is the main oil producing crop?

A

palm oil

68
Q

Where does the cotton come from in the plant?

A

ovule

epidermal cells differentiate to make the long fibres

69
Q

which part of the plant does the dye come from?

A

flower
leaves
roots

70
Q

What are some examples of dye plants?

A 
Indigo 
Bedstraw 
marigolds
crabapple
beetroot
71
Q

Why are the compounds produced by plants useful?

A

pollinators

defense

72
Q

What is the nature of the secondary of metabolites?

A

Alkaloid

Terpenoids

73
Q

What are some aspects of the echidnas?

A

•Spines are modified hairs, fur beneath spines.
•Modified spines on the back of tongue and roof of mouth crush insects.
•Eat invertebrates, ants and termites.
•Eggs hatch after 10 days, gestation 2 weeks (short)- parental care is very brief.
Young then move to a pouch, where they feed on milk- they stay in the pouch for 6 months

74
Q

How many species of Echidnas are there?

A

1 species of short-beaked echidna – Australia
3 species of long-beaked echidnas which are now only found in the mountains of New Guinea, including Zaglossus attenboroughi ‘Sir David’s long beaked echidna’. It is critically endangered, only one level above extinct in the wild.

75
Q

What are some aspects of the platypus?

A
  • First thought to be faked.
  • Webbed feet, hunt for benthic invertebrates by electrolocation- it is passive, the platypus is using sensory organs in its gill to detect the weak electric fields given off by muscle activity, etc, nervous system activity in prey items.
  • 2 eggs / burrow, incubation 10 days, no pouch, 3-4 month lactation.
  • Males have spurs on rear ankles connected to venom glands in thighs.
76
Q

Where is the venom apparatus found in platypus?

A

In echidnas the venom apparatus is present but not functional, but it does work in male platypuses.
The venom gland is behind the rear knee and is connected to a spur on the back of the ankle. It is reported to be very painful for humans and can apparently kill a dog.
It’s believed to play a role in territorial behaviour during the mating season.
In 2008 the platypus genome was sequenced.
It was found to have a similar number of genes to humans and shares milk protein genes with mammals.
Venom protein production has been identified as the product of gene duplications. These same gene families have undergone gene duplication in venomous reptiles and although they have done so independently from platypus they now code for similar venom proteins.

77
Q

What are the origins of the subclass theria?

A

The oldest metatherian fossil found is dated from the cretaceous (125mya) and in 2011, a new eutherian fossil was dated at 160 my old. Smashing the previous record for oldest eutherian by 35 million years. That means that dates associated with previous publications like this one are likely to be less accurate – see split at 148myr
Recent estimates suggest that the prototherian/therian split happened in the late Triassic or early Jurassic, some 200 mya, and that marsupials and placentals split from one another about 168-178 mya.

78
Q

What structure links trituberculates, marsupials and eutherian mammals in subclass Theria?

A

Similarities in tooth structure link trituberculates, marsupials and eutherian mammals in subclass Theria.

It is believed all therians stem from the extinct taxa Trituberculata.
They had a tribosphenic cheek/molar tooth pattern, where there are three principal cusps in a triangle.
It allowed for both shearing and grinding of food and allowed for efficient munching of insects.
This basic tooth ‘design’ is still seen in many therian mammals today, although in others it has evolved into a 4-cusped ‘design’ – we’ll look at teeth a lot more in both practicals…

79
Q

Summarise the class mamalia.

A 
Class mammalia,
subclass prototheria (egg layers – monotremes – 5 extant species)
Subclass theria (live bearers – marsupials and placental mammals) – common ancestor was a trituberculatae beast with tribosphenic cheek teeth great for efficiently crunching insects.
80
Q

What does the study by Nilsson et al tell us about marsupials?

A

This is a lovely study by Nilsson et al and it’s a beautiful piece of integrated biology, it brings together the fossil record, plate tectonics, and also molecular phylogenetics, to understand the evolution of marsupials.
So this is the marsupial family tree some of these groups are probably extinct nowadays, but you can see, at the base of this tree, we have forms that are found in South America today.
In black here, black means Australia, and these Australian groups involved more recently they’re further down the tree and they’re actually
a subset of the South American group.
So this Australian clade is nested within the South American clade.
And these relationships were discovered by doing molecular analyses and, in this case retroposons were analysed, these mobile genetic elements that can be copied and inserted into new locations in an organism’s DNA.
And 53 of these retroposons were sequenced and this phylogenetic tree was produced that shows that Australian marsupials are more recent than South American forms. So South American forms are therefore ancestral.

Nilsson et al wanted to find out exactly what was going on. They looked at the fossil record, they considered plate tectonic models and they also used molecular phylogenetics to trace the history of marsupial mammals.
They analysed 53 retroposons and concluded that the Australian marsupials formed a monophyletic group but that it was nested within the south American marsupial branches of the phylogeny.
This suggests that there would have been a single dispersion event of marsupials from south America to Australia.
But these continents are on the other side of the world from one another so how did they do this?
Well at the time that they diversified South America was connected to Australia via what is now Antarctica. Anyone remember what the southern supercontinent was called? I mentioned it briefly in yesterday’s lecture – gondwana.
When we look at the distribution of fossils we can construct an area cladogram which shows the ranges of marsupial lineages throughout time. If we compare this to a phylogenetic cladogram which is based on changes to morphological characters of the fossils we see that the two match up pretty well giving us a lot of confidence that marsupials living in north America spread to south America before moving to antarctica then onto Australia.
So the molecular findings of Nilsson et al are complimented nicely by two strands of fossil evidence.

81
Q

What does an area cladogram tell us about marsupials?

A

We can look at an area cladogram of these findings and the base of the tree we’ve got North America coming off and South America and Antarctica and Australia.
And we can mirror this with a phylogenetic cladogram and we can see which groups are found, and in ancient North America, we have things called didelphoids.
Then we have the South American didelphoids, South American microbiotheres and Antarctic microbiotheres, that are obviously now extinct, and then the Australian marsupials around today.

82
Q

Summarise marsupial adaptive radiation.

A

§Evolved in Laurasia in the early Cretaceous when Pangaea largely intact, moving west to what is now North America.
§Late Cretaceous - spread to South America, Africa, across Antarctica to Australia when southern continents connected as Gondwana.
§South America and Australia became isolated and marsupials underwent considerable adaptive radiation there.
§>300 extant species in 7 orders.
§Many marsupials became extinct when coexisting with eutherians.
§Recent recolonisation of North America from South America.

83
Q

What are some recent marsupial discoveries?

A

There have been some relatively recent marsupial discoveries too and they have some awesome aboriginal names such as long-footed potoroo (discovered in 1980 - Australia), and two species of tree kangaroo (discovered in the 1990s- New Guinea) named the dingiso and tenkile (ten-kill-ay).

Marsupials are still being discovered today, this is a long footed potoroo founded in 1980 in Australia and in 1994 this dingiso, a tree kangaroo, was discovered in New Guinea.

84
Q

What is the Infraclass Metatheria: marsupials?

A
  • Probably separated from common ancestors with eutherian mammals late in the Jurassic period.
  • Thereafter evolved very different reproductive strategies.
  • Eutherians: intricate placental relationship between foetal membranes and uterine linings.
  • Marsupials also have a placenta, but only makes loose contact with the foetus and it is short-lived.
  • Gestation short (13d opossum – 35d wallaby): cf. 45d shrew – 650d elephant.
85
Q

How do marsupials reproduce?

A

•Newborns poorly developed, but well developed forelimbs.
•Crawl to nipples in the pouch.
•Females can become pregnant during lactation, and embryo can be arrested at blastocyst
stage (embryonic diapause).
•Mother can therefore have Joey at heel, second offspring on another pouch nipple, arrested blastocyst in uterus.

86
Q

What is the opossum genome?

A
  • Monodelphus domestica, genome sequenced in 2007.
  • Advanced immune function genes: the common ancestor of marsupials and eutherian mammals therefore had all the basic building blocks that now make up the human immune system.
  • Most genetic innovations that led to modern eutherian mammals were not new genes but changes in regulatory DNA and other noncoding elements.
87
Q

Summarise the key points related to marsupials?

A

•Marsupial reproduction and examples of adaptive radiation and convergent evolution.
So what should you know from this lecture is that you should know a bit about marsupials, know something about marsupial reproduction, and be familiar with some amazing examples of adaptive radiation and convergent evolution.
Geographic isolation in Australia led to the adaptive radiation of marsupials and we saw the evolution of ecotypes that are convergent in terms of their ecology.
With many of the eutherian mammals that we are more familiar with. And this pattern of geographic isolation adaptive radiation in mammals are returned to when I talk about afrotherians and Xenarthrans

88
Q

What are the Four placental super-orders recognised?

A

Afrotheria
Xenarthra
Laurasiatheria
Euarchontoglires

Those types of molecular analyses have resulted in some completely new groupings among the eutherian mammals.
We’ve seen some great examples of convergent evolution between marsupials and eutherians but there are also excellent examples between eutherians and other distantly related eutherians. Traditional phylogenies based purely on morphology were clearly not very accurate.
It is likely that as molecular phylogentics continues to evolve and improve there will be yet more reshuffling to the placental family tree but at present this is where we stand.
There are currently four main super-orders: Afrotheria, Xenarthra, Euarchontoglires and Laurasiatheria.
And the phylogenetics, the evolutionary history, of eutherian mammals has undergone really radical change in the last 20 years or so, this is largely the consequence of gene sequencing studies.
Initially evolutionary history phylogenetics was based largely on morphological traits.
But morphology is really prone to convergent evolution and it can really mess around with our interpretation of who is related to whom.
Nowadays, there are four super orders recognized within placental mammals, so we have the Afrotherians.
We’ve got this Xenarthans, which are a group that radiated in South America.
We’ve got the Laurasiatheria which radiated in the northern supercontinent of Laurasia.
This group called the Euarchontoglires, which is also probably largely Laurasian in its origin.

89
Q

What are the six orders of Afrotherians recognised today?

A

So there are six orders of Afrotherians were recognized today, the Afrosoricida, which are the tenrecs and the golden moles, the macroscelidea, which are the elephant shrews or Sengis, the tubilidentata, the aardvark, then elephants, hyraxes, du gongs and manatees.
What’s the evidence for these taxa of being related to each other. Well, Initially it was things like single gene features, like a nine base pair deletion in breast cancer gene called BRAC1.
This links together all of the afrotherians and it’s thought that these are actually the oldest clade in the eutherian tree, they’ve got a pretty ancient origin in Africa, probably, radiating from a common ancestor perhaps 105 million years ago, at a time when it’s thought that Africa was isolated.
So one of the really amazing things about mammal evolution is the fact that we can relate all these adaptive radiation patterns, all these diversification patterns to continental drift and we see adaptive radiation kicking off when continents were isolated.

90
Q

What are some aspects of Afrotheria: Elephants?

A

thought that actually there are probably four species.

  • 2 living species (maybe more): African (savannah/ forest) and Indian.
  • Large ears dissipate heat.
  • Trunk is fused upper lip and nose, used in gathering food (neck short).
  • Tusks are elongated upper incisors.
  • Vegetarians.
  • Columnar limbs.
91
Q

Why do elephants have big ears?

A

Well they’ve got a very large volume relative to a surface area so it’s difficult for them to lose heat, so their large ears help them dissipate heat.

92
Q

What are aspects of elephant social organisation?

A
  • Related females live together with immature offspring.
  • Oldest female (matriarch) leads the group.
  • May live to > 50y, benefits?
  • Co-operative defence of the young.
  • Males line alone or in small groups.
  • Communicate over long distances by infrasound.
93
Q

How do naked mole rats reproduce?

A

•Subterranean. Social structure resembles that seen in some social insects.
•In each colony, a single pair breeds.
•Remaining animals belong to castes, distinguished by size and function.
•They are hideous in appearance but they have pretty interesting life histories.
•Sometimes two or three males will mate with females, but always just one female. Breeding.
So naked mole rats live underground and are subterranean a bit like moles. But their social structure resembles that that we’ve seen in some social insects that we call eusocial.
What this means is that in any colony just one pair breeds.
The remaining animals belong to castes. These castes fulfil different functions and pairs of different sizes.

94
Q

What are the Ungulates?

A

Hoofed mammals: traditionally two orders:
•Perissodactyla.
Axis of the foot passes through the 3rd (largest) toe.
Odd-toed ungulates.
Artiodactyla (now cetartiodactyla).
Axis of the foot passes between the 3rd and 4th toes.

95
Q

What are aspects of

Artiodactyl diversity?

A

•Much more speciose and diverse than Perissodactyla.
•352 species in 10 families.
•Three main types:
-Pigs, peccaries and hippopotamuses
-Camels and llamas
-Ruminants
•Ruminants have a fermentation chamber within multi-chambered stomachs to aid with cellulose digestion.

Diversity of Life B (11 decks)

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