The Lion`s mane

The Lion`s mane

1. main objectives

   • 1. why do lions have manes?
   • 2. scientists think manes must have some specialised function because are unique to lions.
   • 3. determine if the mane function is male-male competition, or mate choice, or both.
   • 4. importance of mane characteristics (length and darkness)
   • 5. sexual selection and behavior.
   • 6. why don't all males have the same mane

2. methods

   • Scientists started with different ideas as a guide
     • 1. the mane is sexual dimorphic
       • theory sexual selection / selective traits
         • characterisics evolve under the stress of competition for mates
     • 2. the mane develops at puberty
     • 3. is variable within and between populations
   • previous information
     • sexual selected traits increase reproductive success
       • 1. male-male competition
         • armor
         • weapons
       • mate choice
         • male condition
   • mane might function in 3 ways
     • shield against injury
     • fighting sign
     • nutrition status
   • two hypotheses
     • mane area as a target on fights and wounds will be found there
     • wounds in mane are more fatal
   • photographic achieves- changes in mane
     • iidentify ecological trends
   • behaviour among males and females by length and darkness
     • Dummies
       • life-sized toy lions
         • 1. (short, dark mane)
         • 2. (short, blond mane)
         • 3. (long, dark mane)
         • 4. (long, blond mane)

3. results

   • hypotheses
     • eliminate the wounds that were not inflicted by other lions
       • it didnt support the mane-as shield hypotheses
     • wounds in mane area were not more lethal than in other parts of the body
   • photographic
     • develop their mane under 1 year and during that time the main gains pigment until the color becomes more stable
   • Dummies
     • females prefer dark manes
       • manes acts as a signal to the lions
     • males were sensitive to mane darkness, avoid the darker dummie
     • male sensitive to mane length, avoided too
       • mane length indicate short quality in the form of fighting success

4. Analysis

   • males with better features are better competitors
     • females chose the male by the benefits of the offspring
   • ecological factors
     • mane length
       • injured males are less able for fighting
         • manes length, little relation to dominance
     • mane darkness
       • higher levels of testosterone, more aggressive
         • provide information for other lions.
           • male dominance, female race
           • less likely to be wounded, protection
   • why don't all males have dark mane?
     • Temperature
       • lions with dark mane would be affected by heatstress
         • Global warming