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Tour to Neocene
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Grass-colored predator
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When in a Neocene South America has moved to the south, in more cool latitudes,
the area of a subtropical dry pampas has considerably extended, having substituted
southern part of tropical and subtropical forests. Only due to the large rivers
which are flowing down from Andes, a pampas have not promoted further to the
north.
Conditions of life in a South-American pampas are very favorable for numerous
herbivore animals. Plentiful thickets of grasses are easily restored after
feeding of numerous herbivores, giving new growth the most part of year, except
for unless dry season. Here and there on valleys of the rivers and in foothills
there are woods and bush thickets. But the most part of subtropical South American
plains is occupied with seas of meter height grasses.
One of numerous inhabitants of grasses is the deermara, a large rodent of light
and graceful constitution. Herds of these animals numbering up to half-hundred
individuals, wander on plain, coming into thickets of bushes to have a meal
soft juicy leaves. The basic food of these animals includes graminoids. Deermara
males differ from females by rings of white wool around of eyes. They are peacefully
grazed near to females, there will not come yet a breeding season. Then each
of them will turn to the aggressive sovereign of the harem of several females.
While all herd peacefully eats grass on a coast of the river. One male leaves
herd to browse leaves of high grasses, grown on damp coastal ground. Its meal
interrupts, when one more herbivore, the giant paca noisily lefts bushes. This
animal by the constitution looks more to the capybara, but it is the pig-sized
creature: weight of this female mounts to 200 kg. After her there is a male
weighing, perhaps, about 300 kg. The graceful deermara departs a little aside
but when the spotty giant having horn scutes on cheeks yawns, showing huge
orange incisors, the male headlong rushes to herd. Some deermaras, having caught
his steps, run off in sides, and one animal highly jumps up in air and looks
back. Giant pacas absolutely do not pay attention to these timid creatures.
They run slow by a jog-trot on a coast and hide themselves in bushes.
Every these instants did not remain unnoticed for round yellow eyes observing
animals from a high grass. Some pairs of eyes traced each step of deermaras,
and they have seen everything they wanted to see.
One of deermaras is sick: on its leg there is a large aposteme. Some days ago
this animal had wounded the leg, and the wound had been infected. When the
herd goes, this animal lags behind, appreciablly laming. When deermaras move
through high grass, behind them, becoming transfixed at the slightest alarm
of long-legged rodents, striped grey-brownish-golden shadows run a jog trot.
When they become transfixed, it seems, that here there is nothing, except for
grass stems. But when animals calm down and start grazing, motley shadows slide
among grasses closely and closely to the herd. The encirclement starts to tighten...
The silence was broken off with desperate loud chirp of the motley bird flown
out of a grass. And its red-green colouring of belly in deermara’s eyes was
so unexpected, as flash of lightning in the clear sky. The herd has taken to
their heels, but at this moment from the huge figure of a longbill bird has
literally risen from grass directly for a way of the scared rodents. And at
the same time the same birds were standing up straight in full two-meter growth
around of the herd. Massacre began.
Beaks of giant birds struck selected before deermaras with ruthlessness of
spear and speed of lightning. The most part of speedy rodents nevertheless
was rescued, simply having jumped through heads and backs of monstrous birds,
but some ones could not leave the battlefield. When the herd has run up, on
the ground some animals had remained: the dead deermara having an aposteme
on a leg, the half-dead young animal at whom the chest was punched, and the
adult male with broken backbone. Catch was more than plentiful. Eight huge
birds began to gather around of prey. Having seen them, the male had tried
to run away, but his back legs were helplessly dragged by the ground. One of
birds had stepped on his body a leg and has struck mercies to a head of animal.
And the youngster of the deermara had died of loss of blood in one minute after
killing of the male.
Monstrous birds are the most successful hunters of a pampas. They are similar
to fossil bird Phorusracus by some features, but they are not its relatives.
These birds are herons, huge flightless hunting herons. Their cryptic motley
colouring allows come closely to selected prey, and accuracy of deadly beak
impact is the pledge of success at hunting. Herons of the majority of species
live in large colonies. And these birds had developed collectivism in relations
even more - they hunt in pack. But all collectivism is lost somewhere during
the prey sharing - each bird turns to the greedy egoist and tries to snatch
the big chunk of catch in every way.
Usually birds of group Ciconiiformes are not able to dismember catch, and swallow
it entirely. Few exceptions of this rule are only marabou stork and... the
hunting heron. The beak of a hunting heron is adapted to a partition of catch:
in forward part on its edges tooth-like formations were developed, allowing
to tear meat and skin of prey. Due to such beak the bird literally "saws" soft
tissues from bones, leaving to scavengers wretched leavings of meat. Having
eaten plenty and having filled craws by meat, successful hunters abandon a
battlefield and run to nesting place.
Several kilometers far from hunting lands of herons, on a small island in the
middle of the river there is a heronry, nesting place of these birds. Easily
having overcome channel almost one meter deep, successful hunters come to the
ground of a heronry. And each hunter immediately appears literally attacked
by its own hungry fledglings. The young growth about a meter tall, flapping
by scanty winglets, jumps up, trying to get up to a beak of parent. After fledglings
from behind trees adult birds being on duty on a nesting place appear. Pairs
join together, birds show the favour to each other. The beak, had broke a skull
of the deermara and tore meat of an animal half an hour ago, gently touches
feathers on a head of the partner. Birds touch beaks of each other, and then
simultaneously throw up heads and click beaks, clapping short wings. And fledglings
do not like to wait a meal, and they accompany these scenes of tenderness with
hungry shouts. But now it is not a reason to feed them: in crowd especially
impudent fledgling will easily take not only its own share, but also the another's
one. And pairs of birds accompanied with chirping fledglings, go to nests.
The nest of a hunting heron is built on the ground and represents the rounded
construction slightly pressed from above. It is build of branches collected
on the ground and stolen at neighbours, and is covered by grass and dry leaves.
Having crossed edge of a nest, parents at last pay attention to violently shouting
offspring, and it receives a long-awaited meal. The successful hunter belches
a piece of meat on edge of nest, giving a fledgling the opportunity to tear
and to swallow it itself. And parents at this time are engaged to each other:
clean feathers, repair the nest, feed each other. Sometimes as if exchanging
the meat the partner which had not participating in hunting, submits the partner
in life a branch which is diligently stacked in a nest. Life in group is really
effective when it is accompanied by strengthening of connections between partners.
Therefore a lot of time is devoting to an establishment of hierarchy and strengthening
of connections between nesting partners.
Next day partners vary roles - the nurse turns to the hunter, and the yesterday's
hunter is necessary to look at fledglings. It is not such a simple task: they
have already grown up and easily run across the heronry, constantly getting
involved in fights. Therefore frequently parents should preserve the offspring
against sharp beaks of elder fledglings.
When midday heat comes, fledglings go to shadow and doze, laid on the ground
under bushes. And the parent receives a respite during which it can engage
in itself. Someone is cleaned, someone sleeps, and one of males has gone fishing.
He leaves to shallow water and starts look, where the fish side flashes at
the bottom. Sharp impact of a head and jerk - and the thrown fish shines in
air. The male is successful in fishing - he succeeded to catch and to have
eaten some fishes. Last fish is for the fledgling. Having griped it in a beak,
the giant walks to the nesting place. His descendant has already got hungry,
and a fish is very opportunely to him. But the fledgling has not had time to
tear off even a small piece of the large fish as it is taken away immediately
by a stranger only one week elder. Fight is fastened: fledglings snatch each
other by jaws for a beak and try to tumble adversary down. They still do not
have "teeth" on beaks, therefore such fight is rather safe. When
parents run up to separate fledglings (more precisely - to drive off another's
offspring), fledglings fight downright seriously. And the third fledgling is
quietly eating this fish in bushes, trying to not give itself out with a superfluous
sound. Having cluck beaks against each other, adult birds go away and withdraw
fledglings.
Time passes, and fledglings start to investigate the world. The nesting place
becomes close for them, and all of them glance more often where adult birds
go every day - on a coast of the river. But water while is deep for them, and
they remain at home. And now both parents go to hunting: the young growth is
gluttonous and grows quickly.
Some fledglings investigate a coast of a small island. On a sandy spit they
see a school of small birds came flying to the watering place. They are prairie
pipebirds - usual species of local birds. Usually they meet in prairie, but
once a day they fly to the watering place. And now birds come into water and
greedy drink, lifting heads.
Heron fledglings observe pipebirds from afar. Pipebirds perfectly see them,
but they are not anxious at all: while the young hunting heron will reach them,
they will have time to fly up. But not only young herons observe pipebirds
drinking water.
Sand at the bottom starts to move in dangerous affinity from birds, and soon
the strange barbed creature covered by shell gets out of it. It reminds something
average between crawfish and fish. Some time this creature observes legs of
birds, and then makes a prompt throw. One of birds, shortly having peeped,
instantly disappears under water, and the others promptly fly up in air.
The craycatfish has seized one of birds. Somactids of its fins, operating similarly
to pincers, have caught it’s legs, as if the alive trap. Some time predator
keeps a bird under water while it will sink, and then snaps it and swallows,
widely opening mouth with tiny teeth.
One of fledglings comes into water near to a place where the catfish has drowned
the pipebird. It wanders on a shallow water, and suddenly promptly jumps out
on a coast. On its leg the live trap, another craycatfish, dangles. Trying
to shake unexpected and very painful "present", the young heron draws
attention of neighbours. Fledglings are very curious: is a valuable quality
of the hunter, allowing to study. They try to examine and peck a strange creature,
but it suddenly lets off the bird’s leg and clumsily crawls out in water, pulling
by tail.
Some days later young birds venture to overcome the shoaled channel between
island and river bank. The heronry has become empty, and this year birds already
will not return any more to it. On the river bank there is plenty of interesting
things, here animals unknown to heron fledglings live. Through a high grass
a strange long-tailed creature with a narrow muzzle hastens, waddling on two
paws. It is the shell anteater – armadillo specialized to eating insects. Some
young herons tag after it, and soon one of them pecks animal’s shell. Reaction
of this mammal is immediate: the shell anteater turns around and starts to
run into the taken aback fledglings. Thus it makes fast lunges and waves by
claws of forepaws and grunts loudly. One of young birds appears too close,
and the tip of a claw of the shell anteater puts to it a deep scratch on a
hip: game is finished. Birds recede, and the armored small mammal continues
its way.
And other animal, covered with white spots a short-legged creature, similar,
is not so aggressively. Even opposite, it tries to hide at the sight of young
hunting herons. And this fear of a spotty animal gives confidence to young
birds: it is not dangerous, it is not the enemy, but catch is. And they begin
chase it. Having extended by crescent, they cut off spotty creature’s path
to saving bushes. Edges of crescent approach, and the small mammals is encircled.
One by one young hunting herons try to peck possible prey, but it evades from
their clumsy impacts. And one of them hits small mammal in a leg, and it squeals
shrilly. Having forgotten about care, young birds try to slaughter small mammal
by impacts of beaks. But this imprudence can cost dearly: from bushes some
large heavy animals with spotty backs and large heads are shot up. They are
giant pacas, and the spotty small mammal is their cub. The male of paca with
the big cornificated scutes on cheeks loudly growls and opens the mouth wide,
showing large incisors. But herons are too silly to recede reasonably. And
it dearly manages to them: the massive animal attacks. Three centners of furious
flesh run into one of birds and break its fragile body. The male does not calm
down even then when under his legs the young heron turns to a flat mass of
feathers, bones and blood. He shakes head and growls, and the crest of a long
wool on his back stands on end. The escaped birds abandon this terrible place,
running fast and searching for rescue at parents. For today it is enough vital
lessons for them.
Ability to study is important for hunters - it allows to search for new sources
of food and ways of its catch. Only it is necessary to be attentive. High growth
allows hunting heron to see rather far. Keen sight of this bird pays attention
to everything. And might allows the bird such luxury, as curiosity without
fear to be preyed. Having noticed slowly walking giant paca, one of adult hunting
herons leaves group and starts to watch it. Bird knows, that the clumsy animal
can give out to it the small animals hidden in grass - tasty and harmless catch.
And expectation of a bird is not deceived - the large rodent frightens away
the whole flight of birds. But they do not depart, and are hovering above an
area of rich grass, as if adhered. And the hunting heron decides to check up,
what is there so interesting. Had passed after huge beast, it finds in grass
some conic clay constructions, similar to nests of termites. But termites do
not build their termitariums so closely to each other – it means, these constructions
aren’t their houses. Besides from within the muffled peep is uttering: these
things are nests of prairie pipebirds. They are very firm, as are constructed
of clay and burnt by the hot pampas sun. One nest has cracked - the giant paca
had trod on it. And the heron tries to pick open the damaged nest. Having looked
around, it hangs head and starts to break off pieces of clay of the nest wall.
Unexpectedly the hunting heron feels, that prehensile small claws have seized
skin on its head. In the same second above a head of a feathered predator whistle
is uttering, and air becomes full of flapping of tens wings. The set of pipebirds
is hovering above a head of huge bird. It seems, all world was filled with
these agile birdies. And every bird tries to peck the giant of plains in a
head, closely to eyes. Some birds pinch skin of a heron on a head, diligently
pecking wounds. It is more than predator can stand, and the hunting heron goes
fast to neighbours left far forward. As if on command prairie pipebirds abandon
the predator and are hidden in grass - they don’t like to risk any superfluous
instant.
Hunting heron is the best expert among predators. It hunts so successfully,
that this species had superseded predatory beasts on plains of South America
as fossil birds Phorusracidae have once made it. It survives not only due to
force, but also due to difficult behaviour. It studies and learns lessons from
own victories and defeats. Lessons which are given to the bird by life, pleasant,
unexpected or dangerous, are very important. And the one who will know it and
study diligently, becomes the real lord of a pampas - one bird from ten fledglings.
To the north of a pampas, in valley of the great Amazon river, the kingdom
of woods was stretched. Having completely restored after accident of the end
of Holocene, they grow everywhere where can do it. Forest and the river are
the most productive and rich in life ecosystems. And there life literally is
in full swing.
Bestiary
Craycatfish (Astacidoras chelopterus)

This fish representatives family Doradidae (armored catfishes). Similarly
to modern representatives of family, the craycatfish has the forward part
of body
covered with strong osseous carapace, and along sides line of osseous plates
passes. Length of a fish is up to 50 - 60 cm (the female is larger, the male
is more harmonously and more brightly painted). The forward somactid of a pectoral
fin is very strong and thick, it is separated from other fin and supplied with
the special joint. This somactid has set of sharp spikes on the internal side.
Turning forward, it forms together with lateral part of the head the original "pincers".
In a spawning season males use these "pincers" for fight, but outside
of spawning season "pincers" are used for defense, capture and killing
of catch - fishes and large invertebrates. With the help of "pincers" this
catfish is able to catch birds on a watering place; by fast throw the fish
jumps out from ambush to a bird drinking water, grasps its legs and tries to
drown it. In case of a unsuccessful throw the catfish can, using the same somactid
of a fin as a leg turn around and creep away in water. The fish traps catch,
having dug in ground silt, sand or leaves.
Forward part of a body is flattish, head is large, having wide mouth. Eyes
are large, shifted on the top part of the head, protected by wide spikes. Coloring
of the body is cryptic: grey background with non-uniformly scattered black
and yellowish spots.
The fish spawns in small hole at the bottom of the slow-current river, eggs
and fries are protected by the male.
Hunting heron (Graviardea venatrissa)

After mass extinction in the epoch previous to a Neocene, in ecosystems many
free ecological niches had appeared. So, after herbivores large predators had
become extinct. Simultaneously with occurrence of numerous herbivores of a
Neocene also new predators had developed and evolved. Hunting heron is one
of these predators.
This species of birds is one of the largest ones: height of an adult bird is
up to 2 meters, weight - 60 - 80 kg (female is larger than male). At such sizes
the heron has lost ability to flight: its wings are underdeveloped, not more
chicken’s ones by size. The increase of size is connected with the adaptation
of heron to hunting large ground animals. Having abandoned places of its ancestor’s
inhabiting (bogs and rivers), this bird had adapted to life in thickets of
high pampas grasses successfully hunting rodents, reptiles and large insects.
When rodents began to be increased in size, the heron also "had grown
up". The behaviour of a bird had changed also: it became the running pack
hunter. It had allowed birds to prey much larger catch, than lone predator
can kill.
The body of a bird is adapted to chase and killing of large prey. Legs are
long and strong, fingers are short. The beak is especially remarkable: it is
long, straight, on edges of its forward part were developed large tooth-like
outgrowths, allowing to tear meat or to render serious wounds to chase. Coloring
of the body is cryptic, similar to coloring of bittern (Botaurus) feathering.
Eyes are large, bird has keen sight and hearing.
At hunting this species of heron applies two basic tactics: ambush and pursuing.
Cryptic coloring allows birds to be hidden in grass in immediate proximity
to the planned prey then to attack suddenly, when possible catch will approach
too close itself. Pursuing catch, herons at first creep to it, using cryptic
coloring, and then actively cut the planned prey’s way to herd and drive it,
putting wounds (similarly to predators from canine family (Canidae)). Also
birds successfully fishing on the rivers and lakes. At appearing of flights
of locusts or other large insect species heron are willingly fed with them:
having stretched in line, birds walk on a grass and knock down frightened away
insects by impacts of a beak.
Nesting is on the ground in places protected from other land predators, for
example, on a small island, separated by shallow water from a coast, or in
thickets of prickly bushes. When adult birds go hunting, in a nesting place
always there are some adult birds (as a rule, one partner from pair) for protection
of posterity. In clutch there are 3 - 4 eggs, an incubating lasts about 35
days. Nestlings hatch blind, but covered by down. In 3 days they begin to see
clearly, in 10 days feathers start to appear. Nestlings and fledglings have
no tooth-like outgrowths on beaks. 20-day-aged fledglings freely move in colony.
Parents food nestlings by meat, small vertebrates and fishes. At the age of
6 months "teeth" on a beak of young birds start to grow, and they
start to hunt together with adult ones. Birds become independent at the age
of 1 year, sexual maturity is in 3 years.
Prairie pipebird (Geofurnaria pseudotermita)
The specific name of this small bird of order Passeriformes occurs that this
species of birds builds clay nest, similarly to the ancestor - stovemaker
bird (Furnarius).
But this bird settles not on trees, as at modern stovemakers, but on the ground,
and nests look like termitaries (name "pseudotermita" means "false termit").
Bird is like modern starling in size. Its feathering is motley, the basic background
is brown, on wings, nape and back with short yellow strokes (cryptic coloring).
Belly and feathers under wings are bright, metallic green, throat at males
is bright red. In time of courtship display the male is in air above the unfinished
nest and twitters courtship song - melodious warble. Thus he shows its bright
shining belly. If the female accepts his courtship, she sits down on a nest
and starts to simulate actions of nest-building, runs its beak over the uncompleted
part of the nest. These actions alternate with the actions showing readiness
for pairing: demonstration of a pose of copulating.
During the nesting season birds keep by pairs, nesting in large congestions
numbering up to 40 - 50 nests. The nest is making of dirt and clay, looking
like conic hollow construction. In the bottom part of a nest there is a false
entrance which comes to an end impasse, sideways from it there is a real entrance,
so narrow, that the bird hardly squeezes into it. In a clutch there are up
to 5 eggs. The bird is capable to collective protection of nesting place, a
signal of “the general alarm” - sharp whistle.
Shell anteater (Myrmedillo destructor)

One of few species of edentate group (Edentata, Xenarthra), survived in mass
extinction. The descendant of a modern nine-banded armadillo (Dasypus novemcinctus).
This species of armadillos successfully moved in XX century to territory of
USA and the common expansion of its living area have shown the big adaptive
opportunities of this species. The euryphagy has made possible survival of
this species after decrease of ecosystem efficiency.
The shell anteater is the species specialized to feed by social insects. At
lack of the basic forage animal eats soft plants, carrion and large soft-covered
invertebrates, worms. Powerful shell and cornificate skin on a belly partly
protects animal from stings of insects. The size of animal is about 40 cm,
length of a tail – up to 50 cm, weight up to 10 kg. Jaws are weak, teeth numerous,
but very small. Forepaws are armed with strong long claws (length up to 8 cm),
intended for breaking and digging nests of social insects. The animal can move
on two and on four paws. Being attacked by medium-sized predator, animal defends
actively, making aggressive attacks by forepaws. Attacked by large predators
it prefers to run away or quickly bury itself in the ground, but at absence
of an opportunity to be rescued by a different way animal defends actively.
Solitary animal, keeping activity in gloaming and on dawn. It prefers to hide
in grass thickets at the afternoon, night spends in temporary holes. In the
beginning of rain season the female gives birth to 2 or 4 cubs, always enzygotic
twins. They are capable to follow mother after 4 hours after birth. Newborn
cubs have soft shells hardening to the end of 1-st day of life. Sexual maturity
is at the age of 3 years.
Giant paca (Megapaca deinodonta)

The large rodent of Neocene living in various biotopes - from crude meadows
and rather thin woods up to pampas. An adult individual is the pig-sized animal.
Head is massive, on cheeks there are plates of a cornificate skin under which
there is strongly developed malar arch inherited from an ancestor - modern
rodent paca (Cuninculus paca). Animals use this adaptation during intraspecific
duels, striking each other by head side. In the mouth there are long (up to
15 cm long) orange-colored incisors, successfully available as for getting
of food (plants, fruits, tubers and roots), and for defense against a predator:
the animal prefers to run away, but, protecting the cub or not having a way
to deviation, actively attacks an aggressor and puts terrible wounds by incisors.
Legs are short and strong, the animal is capable to accelerate momentum up
to 50 kms per hour and to make sharp turns on full speed. Claws on fingers
are thick and more similar to hoofs, 3 ones on forepaws and hinder legs, middle
toe is larger than lateral ones. Fingers are covered by the common integument
up to the claws. Tail is very short. Body is covered with a short brown wool
with some white spots on crupper and back. On a back of males the wool is longer,
at irritation and aggression it stands on end. The skin on cheeks of adult
males is light - from yellow to almost white, at females it is dark, a horn
plate is smaller. Cubs keep coloring, characteristic for an ancestor: plenty
of white spots and longitudinal strip along the body; cheeks are covered with
wool.
This rodent keeps by herds on 20 - 30 individuals, among males and females
the hierarchy is observed. Within one year there are about 2 packs. In a pack
there is up to 4 well developed cubs in weight about 5 kg everyone. Cubs are
suckled by all feeding females of herd that provides high survival rate of
posterity. From week age the young growth starts to try vegetative food, at
the age of 1 month completely passes to a diet of adult animals. The young
growth becomes independent at the age of 4 months, sexual maturity comes at
the age of 2 years. Animal lives till 15 years.

This species is the graceful, easily combined herbivore, the descendant of
a modern South-American rodent mara (Dolichotis patagonica). In comparison
with an ancestor it has strongly increased in size (height at a shoulder is
up to 1 meter, length of a body - up to 1.3 m, weight - up to 35 kg). It
does not dig holes, occupies an ecological niche of running herbivores - antelopes
and deer, lives on plains, sometimes comes into light forests. Animal keeps
by herds on 30 - 50 individuals, at a fodder shortage herds break to small
groups on 5 - 6 animals.
Deermara eats grass and leaves of bushes, at fodder shortage can eat ends of
branches and bark of bushes and young trees. It drinks seldom, usually is content
with a moisture received from plants. Due to unpretentiousness and endurance
the present species was widely settled in South America and had passed over
Antilles to the southern part of Northern America, having formed on territories
of semi-deserts and grassy plains the
separate close species distinguished
by more graceful and fragile constitution.
Legs are long, on foot the middle toe, on hand - III and IV fingers are especially
advanced. On these fingers claws have turned to small hoofs. Lateral fingers
concern the ground only a tip. Hind legs are longer than forepaws, croup of
an animal is raised above shoulders. The animal is timidly and cautiously,
runs quickly, accelerating momentum up to 60 kms per hour on a short distance.
During run some animals in herd make single jumps on height up to 2 meters,
looking over district. The neck is rather long, animal resembles by proportions
small deer, for example musk deer (Moschus). The head is similar to rabbit’s
one, eyes are large and ears are long. Near the mouth there are long whiskers.
Tail is not present. Colouring of body is ginger-brown; back is darker and
stomach is white. At males around of eyes there are white rings; head is
colored
darker, than at females. Cubs are similar to the female in colouring. Per
one year female usually gives birth to twin cubs. They are well advanced,
in
some hours after birth are able to follow mother. At the age of 5 months
cubs are completely independent, but keep in herd with parents.