Archive for March, 2010

As far as birds go, the pink flamingo has had its ups and downs.  In ancient times, the pink flamingo waffled between being a delicacy for Roman plates and the living representation of the Egyptian god Ra.  By the 20th century the flamingo became the ubiquitous plastic lawn ornament, forever associated with suburban America, and the unfortunate live croquet mallet in Alice in Wonderland.

I’d like to suggest that there’s some interesting science to be found in this long legged pink bird, beyond lawn aesthetics and sport utility.

For example – Why are pink flamingos pink?  Turns out, it for much the same reason why pink salmon are pink.  Both these animals have a natural diet that is high in shrimp, krill, and blue-green algae.  The pigments in these species, once digested, produces chemicals which are deposited as a pink colour in flamingo feathers and salmon flesh.  Indeed, zoo-fed flamingos are often pale due to an unnatural diet lacking in shrimps and algae.

Or how about this – Why do flamingos stand on one leg?  There are some outlandish theories out there – everything from mitigating gravity effects to increased predation reaction time. More recent research has suggested that the birds alternate standing legs as a way of regulating heat loss while standing in cold water. (Find the original paper here and a briefer summary here). The scientists conducting the study noted that birds stood on one leg most often when they were in water, while preferring to stand on two legs on land.

Of course, this all doesn’t explain the most interesting question – What IS the efficiency of a flamingo croquet mallet versus a wooden croquet mallet??

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Fish Love

Recently, TED.com broadcast a talk by famed chef and amateur scientist Dan Barber, entitled, “How I fell in love with a fish.”  What’s fish love got to do with animal science?  Surprisingly, quite a bit!  Take a look at this link to view the discussion in full:
Dan Barber talks fish love on TED.com.

Fish farming has been both lauded and criticized by the media, social activists, and foodies worldwide.  On the surface, fish farming seems a natural progression.  Why hunt and gather when you can produce?  It is, after all, based on the model of food production that has sustained much of the First World for the last century.  Fish farming is also a viable alternative to the massive overfishing which has decimated many large-fish stocks, such as tuna and cod.  But is it sustainable?  And perhaps most importantly, is there anything remotely “natural” about it?

Productivity of fish farms is often measured in terms of input-output:  How much input is required to produce a certain output of marketable fish?  Some farmed fish species can achieve conversion ratios of close to 1:1, but for most fish, ratios of between 3  to 1 and 10 to 1 are more common.  Incredibly, tuna requires 15lbs  of input to produce 1lb of marketable fish!  These fish are kept in open-water cages or tanks, restricting their normal swimming habits.  As a result, their water must be continually treated for contaminants and the fish must be fed regularly.   A lot of fish feed is produced from the scraps of the livestock industry.  As Dan points out in his talk, we are eating fish who eat chicken!

Dan then compared this typical agri-business fish farm to an eco-farm operating on the coast of Spain.  This fish farm was created on the marshy, flooded canals off the coasts of Spain .  Here, commercial fish, shrimp and eels are raised in an almost-natural marsh setting.  Instead of controlling for oxygen content, nitrogen levels and contaminant levels, the farm relies on the natural cycling processes of the ecosystem and resident organisms.  Perhaps most amazingly, the fish eat… what fish eat!  Algae, phytoplankton, and even other fish are on the menu.  No chicken dinners here.

As researchers and technicians in animal science, we can draw parallels with how we keep our own animals.  We breed mice in massive numbers, we feed them generic, chemically correct diets, plunk them into sterile cages once a week, and then we wonder – Why do I lose 20-40% of pups?  Why do some breeding pairs fail to produce?

No one is advocating a switch to open field mice breeding.  Clearly ,the nature of scientific experimentation does not allow this.  However, we can ask: What steps can we take to make animal breeding more natural?   Mice, for example, typically build nests and forage for foods.  Excellent options for rodent breeding can include adding nesting materials, providing nutritional supplements, and supplying foraging opportunities.  All of these options work by working with the natural tendencies of the rodent.  This idea can be applied to all animals kept in research colonies.  Whether it is through increased enrichment or improved breeding strategies, we might find that by working with nature, we will have more success than when we try to control it.

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