Question: Vaka is the common name for a track and lead single from which band that takes its name from the frontman's sister, Sigurrós Elín?

Context paragraphs:
Horned lizard: Horned lizards are a genus (Phrynosoma) of lizards which are the type genus of the subfamily Phrynosomatinae.  Historically known as the "horny toad", or "horntoad", taxonomists often hypercorrect the English common name to the vague "horned lizard," which can lead to confusion with other horned lizards, such as the bearded dragon, which belongs to a different family.  The common name is a metaphor prompted by the horntoad's flattened, rounded body and blunt snout, which make the common name "horntoad" natural and easy to remember.

Vaka (song): "Vaka" (released as "untitled #1 (a.k.a. "Vaka")") is the common name for the untitled first track and lead single from Sigur Rós' 2002 album "( )".  As late as November 12, 2006, the single remained fifteenth in the Canadian singles chart, having spent a total of 16 weeks in the top 20.

Iris (plant): Iris is a genus of about 260–300, species of flowering plants with showy flowers.  It takes its name from the Greek word for a rainbow, which is also the name for the Greek goddess of the rainbow, Iris.  Some authors state that the name refers to the wide variety of flower colors found among the many species.  As well as being the scientific name, "iris" is also very widely used as a common name for all "Iris" species, as well as some belonging to other closely related genera.  A common name for some species is 'flags', while the plants of the subgenus "Scorpiris" are widely known as 'junos', particularly in horticulture.  It is a popular garden flower.

List of the most common surnames in Germany: Although "Müller" is the most common name in German-speaking countries, in some areas other surnames are more frequent than Müller.  The common names Schmidt and Schmitz lead in the central German-speaking and eastern Low German-speaking areas.  "Meyer" is particularly common in the Low German-speaking regions, especially in Lower Saxony (where it is more common than Müller).  "Bauer" leads in eastern Upper German-speaking Bavaria.  Rarer names tend to accumulate in the north and south.  "Huber" is common in southern Bavaria and is, with the exception of Munich, the most frequent name in that area.  The Patronymic surnames Jansen/Janssen, Hansen, and Petersen are the most common names in the far north (Lower Saxony and Schleswig-Holstein).

List of songs written by Bruno Mars: American singer-songwriter Bruno Mars has written and recorded songs for his studio albums, "Doo-Wops & Hooligans" (2010) and "Unorthodox Jukebox" (2012), and has written songs for other singers.  The Smeezingtons (Bruno Mars, Philip Lawrence, Ari Levine) worked in the majority of the songs in Mars' debut studio album, including writing "Count on Me" and "Marry You" together.  The team collaborated with Khari Cain and Khalil Walton on the album's lead single "Just the Way You Are", peaking at number one on the "Billboard" Hot 100.  Mars explained "I wasn't thinking of anything deep or poetic.  I was telling a story."  Mars co-wrote and co-produced the song "Talking to the Moon" with Grammy Award winning producer Jeff Bhasker.  The single "Grenade", was conceptualised after Mars heard an unreleased track with similar lyrical themes.  Mars' follow-up album, in addition to reunite collaborators from his previous album, such as The Smeezingtons and Jeff Bhasker, included new composers, such as Mark Ronson and Emile Haynie.  All of these producers worked on the lead single "Locked Out of Heaven".  The song concerns a relationship infused with positive emotion and good sex.  The idea behind the second single, "When I Was Your Man", is the regret of letting a girl get away.  Several of the songs were written solely by his production team, including the lead single, "If I Knew" and the single "Gorilla"

Hesperevax acaulis: Hesperevax acaulis is a species of flowering plant in the aster family known by the common name stemless dwarf cudweed.  It is native to California and Oregon where it grows in many types of mountain, valley, and coastal habitats, including areas recently affected by wildfire.  This petite woolly annual forms a small bunch on the ground.  Despite its common name it sometimes has a stem a few centimeters long.  The wool-coated leaves appear in pairs or clusters, each leaf measuring a few millimeters to three centimeters long.  In the center of the leaf array is the inflorescence, which is a single flower head or tightly packed cluster of several heads, each just a few millimeters wide.  The flower head contains several tiny disc florets.

Samantha (Hole song): "Samantha" is a song by the American alternative rock band Hole.  It is the fifth track on the band's fourth studio album, "Nobody's Daughter", released on Mercury Records on April 23, 2010.  Written by vocalist Courtney Love, The Smashing Pumpkins frontman Billy Corgan and music producer Linda Perry, "Samantha" was originally planned as the album's lead single. " Skinny Little Bitch" was later released as the album's lead single on March 12, 2010 and "Samantha" did not receive a single release reputedly due to the controversy over its composition.

Wing-barred seedeater: The wing-barred seedeater ("Sporophila americana") is a passerine bird from coastal regions of north-eastern South America in north-eastern Venezuela, Tobago, the Guianas, Amapá and north-eastern Pará (with a single record from Maranhão), Brazil, and along the Amazon River upstream to around Manaus.  Formerly, it included the mainly Central American "Sporophila corvina" and the west Amazonian "S. murallae" as subspecies, in which case the combined species had the common name Variable Seedeater.  Following the split, this common name is now restricted to "S. corvina".

Sigur Rós: Sigur Rós (] ) is an Icelandic post-rock band from Reykjavík, who have been active since 1994.  Known for their ethereal sound, frontman Jónsi's falsetto vocals, and the use of bowed guitar, the band's music is also noticeable for its incorporation of classical and minimalist aesthetic elements.  The band is named after Jónsi's sister Sigurrós Elín.

Clinus nematopterus: Clinus nematopterus, the Chinese klipfish, that occurs in subtropical waters of the Atlantic Ocean where, despite its common name, it is endemic to South Africa, the common name having derived from a locality error in the original description.  This species can reach a maximum length of 11 cm TL.  This species feeds on benthic crustaceans (amphipods, isopods, ostracods) and also takes other fishes.

Supporting paragraphs: Vaka (song) Sigur Rós
Answer: Sigur Rós