Alarming Avocados

Not all avocados are green and pear-shaped. Some are spherical, black and even purple. Photo by ruurmo. Aguacates para todos. CC. https://flic.kr/p/fN5wX (pile)

Not all avocados are green and pear-shaped. Some are spherical, black and even purple. Photo by ruurmo. Aguacates para todos. CC. https://flic.kr/p/fN5wX (pile)

 

Scooping the flesh out of an over-ripe avocado the other day, I thought, what a weird fruit. The more I researched the avocado, the more I realized that yep, this plant really is weird. Here’s why.

Origin Story

Crazy fact: the avocado was domesticated so long ago that we don’t know what its wild ancestor looked like.

Humans in Mexico were growing avocados long before history was being recorded. They called it ahuacatl, and it’s still called that in some parts of Mexico.

The Incas discovered avocados between 1450 and 1475 when they happened to take over an area where the fruit were grown. The Inca called the fruit aguacate. The fruit was grown from the Rio Grande to central Peru before Europeans arrived.

The European explorers were quick to adopt the aguacate. They liked by the buttery texture but the native name eluded them. Various mangled versions of the name ‘aguacate’ started popping up in European documents.

The avocado quickly spread from Mexico to other areas with the same climate. A bunch were planted in the West Indies. In 1833 they were introduced to Florida, and California got some in 1871. Today avocados are grown around the world, from New Zealand to Indonesia. Mexico is the leading exporter of avocados, followed by California, Israel and South Africa.

How about an alligator pear sandwich?

What do you call a bumpy green fruit? Photo by torbakhopper HE DEAD. CC. https://flic.kr/p/fpwPr

What do you call a bumpy green fruit? Photo by torbakhopper HE DEAD. CC. https://flic.kr/p/fpwPr

Remember how the European explorers had trouble with ‘aguacate?’ Well, the name mangling got worse, as common names often do.

By the beginning of the 20th century, there were at least 40 different names for avocado. These included avigato, albecatta, avocatier, avocatt, midshipman’s butter, vegetable butter, butter pear and my personal favorite, alligator pear. Well, it’s pear shaped and scaly like an alligator, right? Makes sense.

The showdown to choose the correct name happened in the United States. California called the fruit aguacate, while Florida liked alligator pear. Neither of them wanted to change the name. However the powers that be in the U.S. Department of Agriculture decided that alligator pear was unpleasant, and suggested avocado instead. After some scuffles, the name avocado became the industry standard. In a different world, we would have alligator pears in our sandwiches.

A flower with an identity crisis

Avocado flowers. Photo by Cayobo. Avocado Flowers. CC. https://flic.kr/p/zbPB

Avocado flowers. Photo by Cayobo. Avocado Flowers. CC. https://flic.kr/p/zbPB

Avocados make over a million flowers, but less than 0.1% ever become fruit.

Like a lot of flowers, each avocado flower has both male and female organs. Here’s where it gets crazy: the parts don’t work at the same time. The flower only opens for two days. On the first day, only the female organs work. For two to three hours. On the second day, only the male organs work. No other plant does this. I told you avocados were weird. The botany word for this is dichogamous. Isn’t science grand?

Because of this unique pollination system, if a tree is all on it’s lonesome, it’s out of luck. It can’t pollinate itself, so it won’t have any fruit. Growers have to be careful to mix varieties whose male and female organs work at the same time of day. Thankfully there are over 1,000 different avocado varieties, so this isn’t too hard to do.

Berry nice to meet you

The creamy avocado is a fruit, but what kind? Photo by Jaanus Silla. Avocado. CC. https://flic.kr/p/68eBn2

The creamy avocado is a fruit, but what kind? Photo by Jaanus Silla. Avocado. CC. https://flic.kr/p/68eBn2

Avocados are actually berries. In the world of botany, berries are fleshy fruit that grow from a single ovary. Think blueberries, tomatoes, bananas, and even pumpkins.

You can try planting an avocado seed, but it will be five to 13 years before you’ll get a fruit out of it. If you’re impatient like me, you can always pick up one up at a grocery store. It will take 7-10 days to ripen at room temperature. To make it ripen faster, put it in a bag with another ripe fruit like an apple or banana.

Tree time

Avocado tree in bloom. Photo by Cayobo. Avocado Tree In Bloom. CC. https://flic.kr/p/mg7qZw

Avocado tree in bloom. Photo by Cayobo. Avocado Tree In Bloom. CC. https://flic.kr/p/mg7qZw

Avocados grow on trees. They can be up to 60 feet (20 metres) tall, but farmers usually prune their trees to keep them under 15 feet. These trees are tanks. 400-year old wild avocado trees in Mexico are still making fruit.
When a tree is 5-7 years old it yields 200-300 fruit per year. However, the trees like to take a break, so a bumper-crop year is usually followed by a slow year. This can be a problem because avocado demand doesn’t have yearly cycles. People want their guacamole, and they want it now.

Economic boom and bust

The alternating cycle of avocado trees makes life hard for avocado farmers. The industry loses millions of dollars during low crop years. Researchers are trying to find ways of getting the trees to produce the same every year, but no luck so far.

In 1965 California found an innovative solution to the problem of too many avocados in bumper-crop years; freezing then in liquid nitrogen. They could be thawed later to use in restaurants and airlines. Wait, they serve avocados on airplanes? I must be taking the wrong flights.

Sugar or spice. Or both.

People use avocados for all sorts of things, even ice cream. Photo by Kimberly Vardeman. Avocado Ice. CC. https://flic.kr/p/9VsoZE

People use avocados for all sorts of things, even ice cream. Photo by Kimberly Vardeman. Avocado Ice. CC. https://flic.kr/p/9VsoZE

The cool thing about avocados is there is no right way to eat them.

In North America we eat them in salads and sandwiches. In some places in South and Central America an avocado with salt, tortilla and a cup of coffee is a complete meal.

In Brazil, it’s a dessert mixed with ice cream and milkshakes. They have avocado ice cream in New Zealand too. In Java, avocado is mixed with sugar and black coffee.

Ever wonder why we eat avocados raw? Ever thought of cooking one? Well, I wouldn’t try it. Avocados get bitter when they’re cooked, because they’re full of chemicals called tannins.

Weird by-products

Think there's no avocado in this soap? Think again. Avocado oil is popular in lots of products. Photo by Erin Costa. Pink Strawberry Soap_KRISTIE 2. CC. https://flic.kr/p/bmC7W4

Think there’s no avocado in this soap? Think again. Avocado oil is popular in lots of products. Photo by Erin Costa. Pink Strawberry Soap_KRISTIE 2. CC. https://flic.kr/p/bmC7W4

Avocado oil keeps for a long time, up to 12 years at four degrees C. Because of this stability, avocado oil is used to make facial creams, hand lotions and fancy soap. In fact, 30% of the Brazilian crop is made into oil. The leftover flesh is used to feed farm animals once the oil has been squeezed out.
Strangely enough, the avocado’s huge seed contains a white fluid that turns dark red when exposed to the air. The Spanish conquistadors used it as ink.

Now you have something to ponder over your next bowl of guacamole, or avocado milkshake.

References
http://ucavo.ucr.edu/General/ThreeGroups.html
http://ucavo.ucr.edu/General/FruitBerry.html
http://ucavo.ucr.edu/General/Answers.html#anchor738397
http://ucavo.ucr.edu/General/HistoryName.html
http://ucavo.ucr.edu/General/Introduction.html
https://www.hort.purdue.edu/newcrop/morton/avocado_ars.html
http://ucavo.ucr.edu/AvocadoVarieties/Hass_History.html
http://www.britannica.com/EBchecked/topic/45866/avocado
https://www.hort.purdue.edu/newcrop/morton/avocado_ars.html
https://www.hort.purdue.edu/newcrop/morton/avocado_ars.html
http://ucavo.ucr.edu/Flowering/Figure3.html
http://ucavo.ucr.edu/Flowering/FloweringBasics.html

Une interview avec une mésange

Les mésanges vivent dans les bandes hivernales. Photo par Amelia Buchanan, CC.

Les mésanges vivent dans les bandes hivernales. Photo par Amelia Buchanan, CC.

Amelia : Allo mésange, est-ce que vous avez un moment pour me parler?

Mésange : Non. Au contraire je n’ai pas de temps! Il faut que je cache des grains. Je ne peux pas trouver la nourriture pendant l’hiver à l’épicerie, comme les humains.

A : Mais j’ai des graines de tournesol ici, dans ma poche.

M : Ça change tout! Je peux prendre un peu de temps pour te parler.

A : Vous cachez des grains pourquoi?

M : Pour survivre l’hiver, évidemment. Je vais les utiliser quand il fait trop froid pour chercher les insectes. Comme les écureuils, je les cache en abondance l’automne pour les retrouver pendant l’hiver. Contrairement à un écureuil, qui a une mémoire de moineau, j’arrive à me souvenir des locations d’un mille graines que j’ai cachées cinq mois avant. Pas mal pour un petit oiseau, hein?

A : Pas mal du tout. Est-ce que vous cachez les graines sous la terre comme les écureuils?

M : Non, je préfère les placer dans les petits trous des arbres ou en dessous de leur écorce. Il est plus facile de les trouver là que par terre après qu’il ait neigé.

A : Ah, c’est intelligent, ça. À part la nourriture, comment est-ce que vous faites pour survivre aux hivers canadiens?

M : Ca n’est pas facile. Heureusement mes plumes capturent ma chaleur corporelle. Ça fonctionne comme vos sous-vêtements longs. Pendant la nuit je m’endorme dans un trou douillet dans une bûche pourrie. Pendant que je dors, la température de corps baisse de 10-12 degrés Celsius pour économiser de l’énergie.

A : 10 degrés Celsius? J’ai froid quand mon thermostat baisse de deux degrés.

M : T’as froid parce que tu n’es qu’un humain fragile. Laisse-toi pousser des plumes!

A : Hey, ce n’est pas gentil! Je partage mes graines de tournesol, après tout.

M : Désolé. Je deviens plus agressif pendant l’hiver. C’est comment on survit dans notre gang.
A : Attends, il y a des gangs des mésanges?

M : C’est plutôt une bande, mais un gang a l’air plus cool.

A : Alors, combien il-y-a-t-il de mésanges dans ta bande hivernale?

M : Cette année nous sommes cinq : deux couples et un bébé. Il y a aussi un pic et des sittelles, mais ils ne font pas partie de la hiérarchie.

A : Pourquoi est-ce que les autres oiseaux vous rejoignent?

M : Nous connaissions vraiment bien ce territoire. Des fois, des oiseaux migrateurs passent du temps avec nous autres parce que nous connaissons les meilleurs endroits pour manger. Nous les aidons. Nous sommes agressifs, pas méchants.

A : Pourquoi est-ce que vous êtes agressifs?

M : Notre bande a une échelle vraiment stricte. Si vous êtes agressifs, vous mangez en premier et vous avez les meilleurs endroits pour dormir la nuit.

A : Je vois l’avantage. Alors, vous êtes où sur cette échelle?

M : En haut bien sûr. Je suis le mâle le plus vieux. Au printemps je vais trouver un territoire avec la femelle dominant, et avoir les enfants. Nous serons bien nourris, alors nos enfants vont avoir une meilleure chance de survivre.

A : Est-ce que vous aimez les enfants?

M : Pas vraiment. C’est épuisant d’élever les bébés. Nous les nourrissions 6-14 fois par heure. C’est ridicule.

A : Vous avez combien de petits, normalement?

M : Ma femelle pond 5-7 œufs chaque année. S’ils ne sont pas mangés par des serpents, des écureuils ou des belettes, on aura de 5 à 7 bébés à nourrir et à changer.

A : Qu’est-ce que vous voulez dire par changer? Ils ne portent pas de couches, vos petits?

M : Non, mais il faut enlever leur déjections du nid. Et ils en produisent beaucoup!

A : Ah, je vois. Est-ce que vous leurs donnez des grains pour manger?

M : Non. Nous leur donnons des insectes. Les insectes sont 80-90 % de notre alimentation pendant l’été. Même en hiver, ils ne représentent que 50 % de notre alimentation.

A : J’imagine que c’est difficile d’en trouver l’hiver.

M : Je le sais, mais je suis fantastique. Et mignon.

A : Bon, c’est pour cette raison que les gens vous donnent les grains l’hiver. C’est pas mal ta vie!

M : Oui. Merci pour les grains. Je te quitte pour aller persécuter une jeune mésange. À plus!

Les Références
http://www.thecanadianencyclopedia.ca/en/article/chickadee/
http://bna.birds.cornell.edu/bna/species/039/articles/introduction
http://www.hww.ca/en/species/birds/chickadee.html

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