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Wednesday, 21 September 2011

shark attack quickly

do not mess around the shark lol enjoy friends thx 

help save the tiger

first : we should help and poaching : the most bad thing is the trade in tigers skin and body parts this policy will  devastating on tigers numbers . so please we should focus on animals kill for live but why we are killing tigers for example .

second : Support Tiger conservation organisations : many zoos work hardly to save tigers but without our help it will be hard and hard what we should do this is the question please try to post on facebook or on chatting and in fourms about tigers thank you so much

Thursday, 8 September 2011

lions hunt a giraffe

nice video amazing look here :

enjoy thank u

Sexual Selection, Speciation, and Extinction

Some recent thinking about the conservation of biodiversity emphasizes the
processes that create biodiversity rather than the pattern that happens to be
present today (Mace, Balmford, and Ginsberg 1999). Thus, if we wish to
maintain the capacity to create future biodiversity, we need to understand the
processes responsible. Although the influence of behavior in reproductive isolating
mechanisms has long been recognized, it is only recently that substantial
support has emerged for the importance of sexual selection in sympatric speciation.
Studies of bird speciation show that sexually selected clades (those with
greater sexual dimorphism) are more speciose (Barraclough, Harvey, and Nee
1995; Møller and Cuervo 1998). The cichlid species flocks of the African great
lakes are the classical example of a group that has shown explosive speciation
rates under intense sexual selection (Seehausen 2000).
However, while speciation may proceed rapidly under the influence of
sexual selection, the ornamentation or elaborate displays that are generated
by male intrasexual competition or female mate preferences may predispose
populations that possess them to extinction. Despite the theoretical importance
of sexually selected handicaps (Zahavi 1975, Grafen 1990), empirical
information on costs is accumulating only slowly. However, signaling intensity
and the size of display structures have been shown to have correlated energetic
costs in a number of species (e.g., drumming in wolf spiders [Kotiaho
et al. 1998]) and to affect life history traits (scent-marking frequency is
inversely correlated with growth in mice [Gosling et al. 2000]). The best data

on survival are from experiments on barn swallows showing that survival
prospects of males are inversely related to experimentally manipulated tail
length (Møller 1994). There is also evidence that males carry ornaments at
the expense of their resistance to disease and parasites (Folstad and Karter
1992). Although androgens promote the development of male display structures,
they may also suppress immune function. Experimental evidence for a
trade-off between the sexually selected trait and immunocompetence is now
available in birds, including swallows (Saino and Møller 1996; Saino, Bolzer,
and Møller 1997) and domestic fowls (Verhulst et al. 1999). Whatever the
costs of display traits, all models of sexual selection predict that the evolution
of elaborate display traits involves fitness costs that displace males from their
survival optimum (Møller 2000).
Evidence that sexually selected traits affect extinction rates includes data
supporting Cope’s rule (Cope 1896, Eisenberg 1981), which states that body
size tends to increase within evolutionary lineages and that the risk of extinction
increases with body size. Although Cope’s rule does not apply to all taxa,
it probably has some general application (McLain 1993), and since larger
body size is selected for under intrasexual competition, this effect may be
attributed to sexual selection (Møller 2000). Further evidence comes from the
probability of survival of introduced bird populations: McLain, Boulton, and
Redfearn (1995) found that sexually dichromatic species were significantly less
likely to become established than monochromatic species, perhaps because of
the demographic consequences of the more costly sexually selected display
features. A separate study of introduction success in New Zealand has been
variously explained as a result of the degree of sexual dichromatism (Sorci,
Møller, and Clobert 1998) or of demographic stochasticity, influenced by the
mating system and female choosiness (Legendre et al. 1999).
The loss of biodiversity through an effect on sexually selected traits may
sometimes be inadvertent. For example, the processes of sexual selection that
produced the rich diversity of cichlid fishes in Lake Victoria may be
disrupted by pollution (Seehausen, van Alphen, and Witte 1997). In these
species flocks, reproductive isolation is maintained by mate choice using
colorful signals. When these are obscured in turbid water, interbreeding
between species increases and biodiversity is reduced. Similar arguments
involving natural selection have been made by Endler (1997) about changes
in the light environment of forests with consequent effects on the ability of
cryptically colored animals to escape predation.
Other examples where individual fitness may conflict with population
viability occur in cases of sexual conflict where the outcome may be damaging
for one or both sexes and thus for population growth. Male bean weevils
(Callosobruchus maculatus) damage the genitalia of females during copulation

perhaps to help prevent other males from mating with the same female and,
as a result, female survival is reduced (Crodgington and Siva-Jothy 2000). In
evolutionary arms races between the sexes, an adaptation by one sex that gives
it an advantage (for example in mating) is generally matched by a counteradaptation
by the other sex. However, the outcome of such races can sometimes
favor one sex as revealed in a study of water striders (Heteroptera;
Gerridae) (Arnqvist and Rowe 2002). Male water striders attempt to clasp
females during mating using clasping genitalia, and since there is a cost to
females in being clasped repeatedly after fertilization, females develop counteradaptations
such as abdominal spines. The development of these devices and
corresponding behaviors is generally correlated within species, but detailed
studies of morphology and reproductive behavior show that the advantage for
one sex is greater in some species than in others. This leads to differences in
mating rates and thus potentially to differences in population viability.
Sexual conflict is now recognized as being a central process of evolution
with the potential to shape both speciation and extinction rates (Parker and
Partridge 1998, Arnqvist et al. 2000). Such processes can clearly affect population
viability, but are they accessible to conservation intervention? Direct
intervention to prevent animals from damaging each other is possible in conservation
breeding programs (for example, using advanced reproductive
technology) but can anything be done in the wild? In general, it depends on
the ecological circumstances and whether they can be manipulated. In the
example of polygynous antelopes, there is a potential conflict of interest
between males that aim to mate with as many females as possible and females
that wish to choose between males. Thus females often try to leave territories
and males try to herd them back. The ability of males to monopolize females
in this way depends critically on the distribution of resources: where
resources are concentrated, males can monopolize more females and female
choice is more limited. An example is that of male springbok who defend
territories near water holes in arid areas (Ritter and Bednekoff 1995). Such
behavior potentially leads to reduced effective population size and inbreeding
depression, and could be ameliorated simply by providing more water holes.
Intrasexual competition among females may also have a negative effect on
population viability. For example, in some cavity-nesting ducks, high levels
of brood parasitism may result in lower hatching rates in the population
because of inefficient incubation of very large numbers of eggs and disturbance
by parasitic females. These effects appear to cause declining populations
(Eadie, Sherman, and Semel 1998).
These examples raise the issue of when intervention is ethically acceptable.
It is likely to be less acceptable in species in which a sexually selected
benefit to one sex is threatening extinction, but more likely to be acceptable

when an additional anthropogenic factor is exacerbating the threat. Thus, if
the limited availability of water holes artificially increases the benefit to male
springbok at the cost of inbreeding depression, it may be sensible to manipulate
the distribution of water to ameliorate this effect

Adaptive Behavior and Population Viability

have two main benefits: either females gain for their sons those characteristics
that make a male attractive or successful in intrasexual competition, or
females gain viability genes for all their offspring (Andersson 1994). “Good
gene” arguments are often linked to the evolution of display characters since
female choice is often based on the size or elaborateness of male sexual ornaments
or the intensity of males’ displays. These are believed to indicate
viability or fitness, but how? The most influential idea is that selection favors
the evolution of signals that are costly to the signaler because these honestly
reflect the signaler’s quality (Zahavi 1975, Grafen 1990). The issue of signal
costs will be returned to later in the chapter since the evolution of such
“handicaps” may have direct effects on population viability and extinction
probabilities. However, the fitness benefits for individuals from mate choice
(reviewed by Møller, Christe, and Lux 1999; Jennions and Petrie 2000) are
probably concerned principally with the coevolution of parasites and hosts
(Hamilton and Zuk 1982). There is currently much interest in choice as it
relates to genetic variation in the major histocompatibility complex (MHC),
a hypervariable region of the genome concerned with immune function
(reviewed by Jordan and Bruford 1998).
Extensive research on mice shows that mates are chosen on the basis of
their genetic difference from the subject and that this information is
obtained using odors mediated by MHC variation (Potts et al. 1991). The
fact that the MHC is a region concerned intimately with immune function
suggests that the evolution of dissassortative female choice may be favored by
promoting increased disease resistance; for example, through heterozygote
advantage. Alternatively MHC variation may simply act as a polymorphic
marker to minimize inbreeding (Pusey and Wolf 1996).
A problem for arguments that invoke genetic benefits for female choice is
that strong directional selection due to female choice should have depleted
any genetic differences among males (as in the case of a reduction in variation
due to mating skew, as already outlined).Why is there any genetic variation left
among males in the population? This problem, the so-called lek paradox,
remains one of the outstanding problems in evolutionary biology and could
also have direct consequences for population viability. Theoretically, there
should be no additive genetic variance in fitness-related traits (Fisher’s
fundamental theorem), and where selection is strong, as it is in sexually selected
traits, then additive genetic variance should be lower than in nonsexually
selected traits. It is therefore surprising that sexually selected characters
show higher levels of additive genetic fitness than characters not under sexual
selection (Pomiankowski and Møller 1995). What mechanism involving
female choice could promote as well as remove genetic variance in fitnessrelated
traits? The answer has practical as well as theoretical significance if

the variation produced affects population viability. A possible mechanism
(M. Petrie, 2002, pers. comm.) is that female choice could support a higher
than normal mutation rate if the mutational load can be revealed in a display
character. Simulation modeling by G. Roberts and M. Petrie (2002, pers.
comm.) suggests that if females can select males who possess beneficial mutations
but who carry fewer deleterious mutations, then mutation rates 10
times those under random mating can be sustained. The idea that female
choice can maintain mutation rates provides a self-sustaining solution to the
lek paradox and predicts a greater level of evolvability in sexual populations.
This has practical consequences for population conservation since the
persistence of lek breeding may thus be important for population viability.
Lekking in topi is becoming increasingly rare and persists only in the few
remaining high-density populations. In the Mara ecosystem in Kenya it exists
only where grassland is lightly utilized (as inside the Masai Mara Game
Reserve) but not where it is intensively grazed (as outside the reserve with
large densities of livestock). The reason may be that leks form where topi
cluster in short-grass patches for antipredator advantage (Gosling 1986); this
response occurs only where female topi are forced to avoid surrounding
long-grass areas during the resting period of the day and not where the
sward is uniformly short. If lekking is influenced by such relatively simple
habitat features, it may be possible to intervene to help retain this mating
system. Of course it would be desirable to do this in any case because such
striking behavior as lekking in topi deserves to be conserved in its own right.
But it is also possible that such intervention might conserve behavior that
selects for high levels of genetic variation, removes deleterious mutations,
and thus promotes population viability.
The possibility that patterns of mate choice may confer such important
genetic advantages also has general implications for conservation breeding
programs. At present most breeding programs of rare animals in captivity
simply attempt to maximize outbreeding to retain as much genetic variation
as possible. However, for the reasons already discussed here and by Wedekind
(2002a) the benefits of allowing natural choice should be given careful consideration.
In practice this could be achieved either by allowing females to
choose mates or by artificial selection of mates according to the sort of criteria
suggested by recent research on mate choice (e.g., using estimates of MHC
similarity). Recent research suggests that not only might natural mate choice
prevent inbreeding, it might also be driven by genetic compatibility between
potential mates that provides resistance against particular pathogens
(Wedekind et al. 1996, Rülicke et al. 1998). Although this latter possibility
requires further investigation before its consequences are implemented in
conservation breeding programs, there are already grounds for believing that

benefits may be derived from allowing natural mate choice. Thus, where possible,
and in species with appropriate mating systems, allowing choice should
supersede breeding principles based on maximizing outbreeding since
achieving high levels of heterozygosity may not outweigh the costs of accumulating
deleterious mutations. The possibility that all potential mates will
prefer one individual, thus leading to the prospect of severe inbreeding depression,
is unlikely because assortative patterns of mating should generally be
more common. Direct natural choice should be used wherever possible, but in
intensively managed systems this may not be possible. Examples include small
declining wild populations where intervention is essential, or captive populations
where the financial cost of providing a natural choice is high. In these
cases choice of olfactory signals (particularly scent marks, which can be frozen
and shipped among cooperating zoos) provides the greatest promise. These
odors provide subtle information about genetic variation in potential mates
(reviewed by Gosling and Roberts 2001) and they could provide powerful
measures of mate preference if used in properly designed choice assays.

The Role of Animal Behavior in Wildlife Management

It is important to define the role that animal behavior can play in wildlife
conservation and management. Problems in wildlife management are a subset
of the global environmental problems that are of interest to conservation
biology. Major ecological problems include the wholesale loss of species
through habitat destruction; the pollution of air, soil, and water; the introduction
of exotic species (including domestic animals, parasites, and
pathogens); and the alteration of global biogeochemical cycles. Knowledge of
animal behavior is not the sole key to solving global conservation problems;
but then, paradoxically, neither is any branch of ecology or any other science.
Indeed, biologists do not make the important decisions that affect species

extinction and people’s continued ability to benefit from functional ecosystems.
Such decisions are the purview of politicians and business leaders, who
are primarily interested in political and economic goals and are therefore
much more influenced by political and economic processes than by science
(Morowitz 1991).
Changes in socioeconomic circumstances are also important. For example,
immediately following World War II, agriculture was the main occupation in
several southern European countries. People were widely distributed over the
countryside. Almost all natural resources were exploited, including lands
with low productivity. Following industrialization in the mid-1960s, much of

CHAPTER 1—General Introduction

the land that was either hilly or mountainous was abandoned as people
sought a more comfortable lifestyle in cities. Space and resources in the
abandoned countryside became available for wildlife. Urbanization may thus
explain the recent recovery of wildlife in Europe more than any other
economic or biological process. In North America, increased affluence, good
rural road networks, and ability to work from home are instead leading to
suburbanization of wildlife habitat, with negative consequences for biodiversity,
especially of large predators.
Everyone can make “minor” decisions with environmental consequences,
from not eating seafood caught with methods causing extensive bycatch of
nontarget species, to not building a home on critical habitat, to family planning,
to voting patterns in democratic societies. Zoologists, including animal
behaviorists, clearly play a major role in the conservation of biodiversity by
informing decision makers and the general public about the ecological
consequences of human activities. Solving the global conservation problems
that threaten our quality of life, and in some cases our very lives, will require
scientific knowledge, but first and foremost it will require a better system of
economic valuation of goods and services. Economic externalities such as
pollution, habitat destruction, and the loss of ecological functions (including
those that provide clean air, safe drinking water, and a stable climate) must
be incorporated in the evaluation of different activities (Chichilnisky and
Heal 1998). Perhaps the greatest contribution that ecologists can make to
environmental conservation is to convince decision makers at all levels, from
heads of state to individual consumers, to think about the long-term consequences
of their decisions.
Behavioral ecologists typically study the long-term evolutionary consequences
of different animal behaviors. As a result, when examining the
consequences of human actions, they usually consider a longer timescale
than the few years to the next election, or this year’s balance sheet, or the
time it takes to win one particular court case. It is essential that they transmit
such long-term thinking to other sectors of society.
Students of animal behavior can provide an extremely important
approach to wildlife conservation because of their tendency to examine individual
differences, to emphasize the role of variability, and to think in terms
of trade-offs between different behavioral strategies. Such emphasis on the
behavior of individuals and the strategies they adopt to maximize fitness
plays an important role when a species’ natural behavior can lead to conservation
problems in habitats altered by humans. In extreme and rare cases,
the best management strategy may be to interfere with a species’ natural
The study of animal behavior is most usefully applied to the conservation

animal behavior and wild life conservation

why animal behavior is important for conservation

General Introduction:

Many of the species with whom we share our planet are going extinct
because we overexploit them or destroy their habitat (Ehrlich and Wilson
1991, Caughley 1994). Species extinction and habitat destruction have an immediate
impact upon many economic and social activities because various
uses of wildlife provide income, enjoyment, or recreation for millions of
people (Geist 1994). It is therefore not surprising that interest in the conservation
of biodiversity is increasing among the general public as well as
among behavioral ecologists who study wild animals and their environment.
Two related disciplines, wildlife conservation and wildlife management,
use ethological knowledge to limit the impact of humans on ecosystems.
Wildlife conservation is concerned with the preservation of species and their
habitat in the face of threats from human development. Wildlife management,
including fisheries management, seeks sustainable strategies to exploit
wild species while ensuring their persistence and availability for future use.
Ideally, these strategies should also not damage components of the ecosystem
other than the exploited species. Although the distinction between the two
disciplines is often blurred, wildlife management is often oriented toward
specific objectives for one or a few species of economic interest. The goals of
conservation are broader and include the preservation of genetic diversity so

PART I—Why Animal Behavior Is Important for Conservation
that species will maintain their ability to evolve in response to environmental

change. Recently, however, wildlife conservation and management are
coalescing into a single discipline. Management is often a component of
conservation strategies (for example, limited sport harvest of some highprofile
species can be used to generate funds for habitat preservation [Lewis
and Alpert 1997]), and the conservation of genetic diversity or interpopulation
connectivity is often a goal of wildlife management. For simplicity, we will
use the term management in this introduction to refer both to situations
where wild animals are the subject of some form of exploitative management,
and to situations where they are of concern because they are at risk of
Regardless of how one defines wildlife management or wildlife conservation,
however, practical application of these terms inevitably involves the consideration
of both animal and human behavior. This book explores how
knowledge of animal behavior can help prevent species extinction and
sustainably exploit wildlife populations. It is clear to us, however, that human
behavior plays a far greater role than animal behavior in both conservation
and management.