Swallowtail Butterfly Mimicry

While I was out to the garden, collecting a sprig or two of parsley for a veggie stir fry, I was startled by a beautiful caterpillar:

When I looked closer, there were over 10 of them in my parsley patch.

After some investigation, I identified them as the Eastern Black Swallowtail Butterfly (Papilio polyxenes) caterpillar.

They start as a little greenish-yellow iridescent egg, from which emerges after 4 to 9 days, depending on the weather, a black larvae, with a conspicuous white saddle, which mimics bird droppings. This stage lasts 10 to 30 days, and includes several instar phases and a caterpillar.

https://s-media-cache-ak0.pinimg.com/736x/7d/bc/10/7dbc104ea2a0febc2535a05f54c1c452.jpg

Another 9 to 18 days, as a pupa, are needed to become a butterfly.

Black swallowtail butterflies frequent the zinnia garden, 

but wait, after some double checking, I find these butterflies are NOT Eastern Black Swallowtails, but a dark morph of the female Eastern Tiger Swallowtail (Paplio glaucus) and their caterpillar looks like this:

https://en.wikipedia.org/wiki/Papilio_glaucus

Female Eastern Tiger Swallowtails are dimorphic and this chart from Wikipedia shows the differences :

3 - dorsal female dark morph; 6 - ventral female dark morph

"In the dark morph, the areas that are normally yellow are replaced with dark gray or black. A shadow of the "tiger stripes" can be seen on the underside of the some of the dark females."

From one of the photos above, I zoomed in closer, and indeed, you can see the "tiger stripes":

So the differences are easier to identify, pictured below together are the female Eastern Black Swallowtail and then the female Eastern Tiger Swallow tail- dark morph.

Note the prominent white spots on the body and wings, for starters.

https://en.wikipedia.org/wiki/Papilio_polyxenes

Eastern Black Swallowtail (Papilio polyxenes)

Eastern Tiger Swallowtail - dark morph (Papilio glaucus)

There is also a Spicebush Swallowtail (Papilio troilus), which also looks similar:

https://en.wikipedia.org/wiki/Papilio_troilus

and all these dark swallowtails are mimicking the poisonous Pipevine Swallowtail (Battus philenor)

This is called Batesian mimicry, where the butterfly's resemblance to a noxious one, protects it from predators.

There are numerous interesting scientific articles on the subject, but these two studies are especially relevant. In Evolution (33 (1) March 1979), "Batesian Mimicry: Field Demonstration of the Survival Value of Pipevine Swallowtail and Monarch Color Patterns" by M.R. Jeffords, it was shown that mimetic swallowtail butterflies have longer survival times, and are less frequently and vigorously attacked by predators.

Also, why are only the females mimetic? 

In an article in Trends in Ecology and Evolution, titled "Diversity in mimicry: paradox or paradigm", by M. Juron, three possibliities are offered, including 1. being mimetic reduces mating success in males, 2. reduces success competing against other males and 3. since females are more vulnerable to predators because of their predictable behavior while feeding, mimicry would offset this. 

Here is a link to the full article: 

https://www.researchgate.net/profile/James_Mallet/publication/222493255_Diversity_in_mimicry_Paradox_or_paradigm_Trends_Ecol/links/0046351957a31efe09000000.pdf

A simple visit and observation in the garden led to just a peek 

into such a fascinating and 

complex world. 

Spring Discoveries

It is a blustery, damp, dreary, cold Spring day. It's hard to believe, that it's the end of April. Despite the cold, there are some interesting discoveries, that have been awaiting me in the garden.

First Discovery/Confirmation:
Look what was sparkling amongst the weeds:

Raspberry Dressing Lettuce!!

This is a keeper and something I will be sure to plant yearly!

(Check out the earlier entry on October 28th, 2015)

Second Discovery/Confirmation: 

- The zinnia bed covered in old zinnia stocks did well. Just a few weeds, but overall the soil is in place and in excellent shape. The left over seeds were enjoyed by the over-wintering birds, as well.

- The beds covered in black plastic are in great shape, although the soil was more compacted and reduced. In any case, the soil is like black chocolate cake: moist, crumbly and deliciously perfect for planting new spring plants. 

- The beds covered in weed barrier did not fare well. The barriers were not anchored well enough and simply blew away. Those beds are covered in weeds. Argh!  (See previous post on October 25, 2015)

Spring plantings are well underway. I've planted red, romaine and bibb lettuces and parsley plants and pea seeds and mounded starter potatoes. I threw in a tomato and some eggplant just for fun, but it's been too cool for them to make much progress. 

Protect Your Living Soil for the Winter!

After attending a seminar titled, The Down and Dirty: Soil Building Secrets for Greener Gardens by Elizabeth Murphy of Oregon, who has recently published a book called: Building Soil: A Down to Earth Approach, I decided to reevaluate how I put my gardens to bed for the winter.  

I liked how she explained, that soil is a collection of living organisms that comprise the first few inches of soil and need to be cared for like any organism. It has the same basic needs including: water, food, air and shelter/space. During the winter, soil and its organisms need to be protected from exposure and erosion.

I was inspired to try another way to care for my garden soil during the winter. In the past, I have tried a cover crop such as buckwheat, which she advocates for, but I found it unwieldy to deal with in the spring. I tried covering it with black plastic and was fairly satisfied with this approach, but there are no added nutrients with this method. However, there were fewer weeds and the soil was protected. 

Instead of taking all the spent and dead plants and the nutrients that they embody out of the garden in the fall and taking them to the compost pile, why not leave them in place and compose them there directly. So, with my cutting flower bed, I have left the zinnias in place. The birds, overwintering or who haven't left on migration, have continued to feast on the left-over seeds. This will protect the soil from wind and rain, and the blowing or washing away of all the nutrients or compacting by pounding rains or snow.

I have covered another bed with black plastic for comparison sake. I was surprised to see who was sneaking about. Note the large turkey prints!

She has lots of great ideas, including fall cover crops such as clover and using cardboard, 

all ideas I would like to try next fall. 

Here is a story well worth reading: 

http://www.gardenista.com/posts/dirty-secrets-10-ways-to-improve-garden-soil

Here is a link to her blog: 

http://dirtsecrets.com/secrets/